EXC



us-gaap:CommonStockValue

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:CommonStockSharesOutstanding

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:Revenues
dei:LegalEntity
dei:LegalEntity, us-gaap:ConsolidationItems
dei:LegalEntity, us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:PublicUtilityRegulatedOrUnregulatedStatus
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:OperatingExpenses
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingIncomeLoss
dei:LegalEntity

us-gaap:InterestExpense
dei:LegalEntity

us-gaap:OtherNonoperatingIncomeExpense
dei:LegalEntity

us-gaap:NonoperatingIncomeExpense
dei:LegalEntity

us-gaap:IncomeTaxExpenseBenefit
dei:LegalEntity
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:ComprehensiveIncomeNetOfTax
dei:LegalEntity

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest
dei:LegalEntity

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity
dei:LegalEntity
us-gaap:NetIncomeLoss

us-gaap:Assets
dei:LegalEntity
dei:LegalEntity, us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:Liabilities
dei:LegalEntity

us-gaap:LiabilitiesAndStockholdersEquity
dei:LegalEntity

us-gaap:StockholdersEquity
dei:LegalEntity
dei:LegalEntity, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:AssetsCurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:CashAndCashEquivalentsAtCarryingValue
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:AccountsReceivableNetCurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity
dei:LegalEntity
us-gaap:InventoryNet

us-gaap:PropertyPlantAndEquipmentNet
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
dei:LegalEntity
dei:LegalEntity, us-gaap:PropertyPlantAndEquipmentByType

us-gaap:LongTermInvestments
dei:LegalEntity

us-gaap:Goodwill
dei:LegalEntity

us-gaap:OtherAssetsNoncurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:LiabilitiesCurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:AccountsPayableCurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:TaxesPayableCurrent
dei:LegalEntity

us-gaap:OtherLiabilitiesCurrent
dei:LegalEntity

us-gaap:RetainedEarningsAccumulatedDeficit
dei:LegalEntity

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
dei:LegalEntity

us-gaap:OtherLiabilitiesNoncurrent
dei:LegalEntity
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:RepaymentsOfLongTermDebt

us-gaap:NetCashProvidedByUsedInOperatingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInInvestingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInFinancingActivities
dei:LegalEntity
dei:LegalEntity
us-gaap:NetIncomeLoss

us-gaap:DepreciationDepletionAndAmortization
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet
dei:LegalEntity

us-gaap:CashAndCashEquivalentsPeriodIncreaseDecrease

exc:AmortizationOfDebtFairValueAdjustment

exc:AmortizationOfRegulatoryAssetDebtCosts

exc:AmortizationRateStabilizationDeferral
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
exc:CashRemittedToVIE
dei:LegalEntity
exc:ChangeReceivablesPayablesFromAffiliates

exc:ChangesInOptionPremiumsCollectedReceived

exc:EffectiveIncomeTaxRateReconciliationChangeinEnactedTaxLawPercent

exc:EffectiveIncomeTaxRateReconciliationQualifiedDecommissioningInvestmentIncomePercent

exc:EnergyRelatedOptions
dei:LegalEntity
exc:EstimatedPercentOfGasPurchasesBeingHedged
dei:LegalEntity, us-gaap:Range
exc:ExpectedGenerationHedgedInNextTwelveMonths
dei:LegalEntity, us-gaap:Range
exc:ExpectedGenerationHedgedInYearThree
dei:LegalEntity, us-gaap:Range
exc:ExpectedGenerationHedgedInYearTwo
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
exc:FairValueInputsForwardHeatRate
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
exc:FairValueInputsRenewableFactor
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossChangeInCollateral
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInNoncurrentPayablesToAffiliates
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInRegulatoryassets

exc:GainLossInvestmentIncomeNuclearDecommissioningTrustFunds

exc:ImpactsEnergyInfrastructureModernizationAct
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
exc:IntersegmentRevenueNetOfPurchasePowerAndFuel
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
exc:NuclearFuelAmortization
us-gaap:StatementEquityComponents
exc:OtherComprehensiveIncomeUnrealizedGainLossOnEquityInvestmentsArisingDuringPeriodTax

exc:OtherComprehensiveIncomeUnrealizedIncomeLossOnEquityInvestmentsArisingDuringPeriodNetOfTax

exc:OtherDecommissioningRelatedActivity

exc:OtherNoncashIncomeExpenseNet

exc:RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsNonregulatoryAccounting

exc:RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsRegulatoryAccounting

exc:RegulatoryOffsetNuclearDecommissioningTrustFundActivity
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
exc:RevenueNetOfPurchasePowerAndFuelFromExternalCustomers
us-gaap:StatementBusinessSegments
exc:RevenueNetofPurchasePowerAndFuel

exc:UnrealizedGainLossNuclearDecommissioningTrustFundsNonregulatoryAccounting

exc:UnrealizedGainLossNuclearDecommissioningTrustFundsRegulatoryAccounting

exc:UnrecognizedTaxBenefitsInterestIncome

us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities
dei:LegalEntity
us-gaap:AdjustmentsToAdditionalPaidInCapitalOther

us-gaap:AmortizationOfFinancingCosts

us-gaap:AmortizationOfIntangibleAssets

us-gaap:AmortizationOfNuclearFuelLease

us-gaap:AmortizationOfPowerContractsEmissionCredits

us-gaap:AmortizationOfRegulatoryAsset

us-gaap:AssetRetirementObligationAccretionExpense
dei:LegalEntity
us-gaap:AssetRetirementObligationPeriodIncreaseDecrease

us-gaap:AssetRetirementObligationRevisionOfEstimate

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CommonStockDividendsPerShareDeclared
us-gaap:ConsolidationItems
us-gaap:CompetitiveEnergyRevenue

us-gaap:ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress

us-gaap:ContractWithCustomerAssetReclassifiedToReceivable

us-gaap:CostOfGoodsAndServicesEnergyCommoditiesAndServices

us-gaap:CostOfPurchasedPower

us-gaap:CostsAndExpenses

us-gaap:DeferredIncomeTaxesAndTaxCredits
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:DefinedBenefitPlanContributionsByEmployer
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:Depreciation

us-gaap:DepreciationAmortizationAndAccretionNet
dei:LegalEntity
us-gaap:DistributionMadeToLimitedLiabilityCompanyLLCMemberCashDistributionsDeclared

us-gaap:DividendsCommonStockCash

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationDeductionsOther

us-gaap:EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsOther
dei:LegalEntity
us-gaap:ElectricUtilityRevenue

us-gaap:ElectricalGenerationRevenue
dei:LegalEntity
us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
us-gaap:FairValueAssumptionsExpectedVolatilityRate
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
us-gaap:FairValueInputsDiscountForLackOfMarketability
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPeriodIncreaseDecrease

us-gaap:GainLossOnInvestments

us-gaap:GainLossOnSaleOfOtherAssets

us-gaap:GainLossOnSalesOfAssetsAndAssetImpairmentCharges
dei:LegalEntity
us-gaap:GasDomesticRegulatedRevenue

us-gaap:ImpairmentOfLongLivedAssetsHeldForUse

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions

us-gaap:IncreaseDecreaseCashCollateralFromCounterparties

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable
dei:LegalEntity
us-gaap:IncreaseDecreaseInDueToAffiliatesCurrent

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInReceivables

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestExpenseRelatedParty

us-gaap:InterestRevenueExpenseNet

us-gaap:InvestmentIncomeInterest
us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:FairValueByAssetClass, us-gaap:StatementEquityComponents
us-gaap:MarketableSecuritiesUnrealizedGainLoss

us-gaap:MinorityInterestPeriodIncreaseDecrease

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic
dei:LegalEntity
us-gaap:NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax
dei:LegalEntity, us-gaap:StatementEquityComponents
us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossTax
us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve
us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherDepreciationAndAmortization

us-gaap:OtherLaborRelatedExpenses

us-gaap:OtherNoncashIncomeExpense

us-gaap:OtherNonoperatingIncome
us-gaap:ConsolidationItems
us-gaap:OtherOperatingIncome

us-gaap:PaymentsForProceedsFromOtherInvestingActivities
dei:LegalEntity
us-gaap:PaymentsOfDistributionsToAffiliates

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsToAcquireOtherInvestments

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PensionAndOtherPostretirementBenefitContributions

us-gaap:PensionAndOtherPostretirementBenefitExpense
dei:LegalEntity
us-gaap:ProceedsFromContributionsFromParent

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess

us-gaap:ProceedsFromSaleAndMaturityOfOtherInvestments

us-gaap:ProceedsFromSaleOfPropertyHeldForSale

us-gaap:ProceedsFromStockPlans

us-gaap:ProfitLoss

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
dei:LegalEntity, us-gaap:PublicUtility
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount

us-gaap:RealEstateTaxExpense
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass
us-gaap:RealizedInvestmentGainsLosses
us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:RegulatedOperatingRevenue
dei:LegalEntity
us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty
dei:LegalEntity
us-gaap:RelatedPartyTransactionPurchasesFromRelatedParty
us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve
us-gaap:RestructuringAndRelatedCostIncurredCost
us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve
us-gaap:RestructuringReserveAcceleratedDepreciation

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax
us-gaap:ConsolidationItems
us-gaap:RevenueFromPurchasedOilAndGas
dei:LegalEntity
us-gaap:RevenueFromRelatedParties
dei:LegalEntity, us-gaap:ConsolidationItems
us-gaap:SalesRevenueServicesGross

us-gaap:ShareBasedCompensation

us-gaap:StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensationGross

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensationGross

us-gaap:TaxesExcludingIncomeAndExciseTaxes

us-gaap:UnrealizedGainLossOnDerivatives
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:UnrealizedGainLossOnSecurities

us-gaap:UnrecognizedTaxBenefitsPeriodIncreaseDecrease
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseGasAndPetroleumPurchased

us-gaap:UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses
dei:LegalEntity
us-gaap:UtilitiesOperatingExpensePurchasedPower

us-gaap:UtilitiesOperatingExpenseTaxes

dei:EntityCommonStockSharesOutstanding

exc:AccruedCompensationCurrent
dei:LegalEntity
exc:CashCollateralHeld

exc:CashCollateralPosted
dei:LegalEntity, us-gaap:HedgingDesignation
exc:CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentLiability
dei:LegalEntity, us-gaap:HedgingDesignation
exc:CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentNoncurrentLiability
dei:LegalEntity, us-gaap:RelatedPartyTransactionsByRelatedParty
exc:DueFromAffiliateCurrentElectricGasUtility
dei:LegalEntity, us-gaap:RelatedPartyTransactionsByRelatedParty
exc:DueFromAffiliateCurrentElectricUtility
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
exc:FairValueInputsForwardGasPriceAssets
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique
exc:FairValueInputsForwardPowerPriceAssets
us-gaap:FairValueByAssetClass
exc:FairValueNetAssetsLiabilitiesExcludedFromNuclearDecommissioningTrustFundInvestments
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
exc:FinancialAssetLiabilitiesNetFairValueDisclosure1
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
exc:FinancialAssetsFairValueDisclosure1
dei:LegalEntity
exc:IncrementalCollateralForLossOfInvestmentGradeCreditRating
dei:LegalEntity, exc:CreditRiskExposure
exc:InvestmentGradeExternalCreditRating
dei:LegalEntity, exc:CreditRiskExposure
exc:InvestmentGradeInternalCreditRating

exc:InvestmentsInNonconsolidatedVariableInterestEntities
dei:LegalEntity
exc:LettersOfCreditHeld

exc:LettersOfCreditPosted
dei:LegalEntity
exc:MgpSiteContingencyApprovedCleanupCount
dei:LegalEntity
exc:MgpSiteContingencyCount
dei:LegalEntity
exc:MgpSiteContingencyMonitoringCount
dei:LegalEntity
exc:NetAssetLiabilityPositionAfterContractualRightOfOffset
dei:LegalEntity, exc:CreditRiskExposure
exc:NonInvestmentGradeExternalCreditRating
dei:LegalEntity, exc:CreditRiskExposure
exc:NoninvestmentGradeInternalCreditRating

exc:NumberOfVariableInterestEntitiesConsolidated

exc:NumberOfVariableInterestEntitiesNotConsolidated

exc:OtherNonconsolidatedVariableInterestEntityOwnershipInterests
dei:LegalEntity, exc:CreditRiskExposure
exc:TotalCreditRiskExposure
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
exc:TotalDeferredCreditsAndOtherLiabilities

us-gaap:AccountsPayableRelatedPartiesCurrent
dei:LegalEntity
us-gaap:AccountsPayableRelatedPartiesNoncurrent
dei:LegalEntity
us-gaap:AccountsReceivableRelatedPartiesCurrent
dei:LegalEntity
us-gaap:AccountsReceivableRelatedPartiesNoncurrent

us-gaap:AccrualForEnvironmentalLossContingenciesGross
dei:LegalEntity
us-gaap:AccruedLiabilitiesAndOtherLiabilities

us-gaap:AccruedLiabilitiesCurrent
dei:LegalEntity
us-gaap:AdditionalPaidInCapital

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AllowanceForDoubtfulOtherReceivablesCurrent
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementFrequency
us-gaap:AlternativeInvestmentsFairValueDisclosure
dei:LegalEntity, us-gaap:PublicUtility
us-gaap:AssetRetirementObligation
dei:LegalEntity, us-gaap:PublicUtility
us-gaap:AssetRetirementObligationCurrent

us-gaap:AssetRetirementObligationsNoncurrent
dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:AssetsNoncurrent

us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent

us-gaap:CapitalizedCostsAssetRetirementCosts
dei:LegalEntity, us-gaap:BalanceSheetLocation
us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
dei:LegalEntity, us-gaap:ShortTermDebtType
us-gaap:CommercialPaper

us-gaap:ContractWithCustomerAssetNetCurrent

us-gaap:ContractWithCustomerLiabilityCurrent
dei:LegalEntity
us-gaap:CustomerDepositsCurrent
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:DebtInstrumentFairValue

us-gaap:DecommissioningFundInvestments

us-gaap:DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DeferredCompensationLiabilityCurrentAndNoncurrent

us-gaap:DeferredCostsAndOtherAssets

us-gaap:DeferredCreditsAndOtherLiabilities

us-gaap:DeferredFinanceCostsNet

us-gaap:DeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent
dei:LegalEntity
us-gaap:DeferredTaxAssetsLiabilitiesNetNoncurrent

us-gaap:DefinedBenefitPensionPlanLiabilitiesNoncurrent
dei:LegalEntity
us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent

us-gaap:DerivativeAssetNotionalAmount
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeAssets

us-gaap:DerivativeAssetsCurrent

us-gaap:DerivativeAssetsNoncurrent

us-gaap:DerivativeCollateralObligationToReturnCash

us-gaap:DerivativeCollateralObligationToReturnSecurities

us-gaap:DerivativeCollateralRightToReclaimCash
dei:LegalEntity
us-gaap:DerivativeCollateralRightToReclaimSecurities
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeFairValueAmountOffsetAgainstCollateralNet
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral
dei:LegalEntity
us-gaap:DerivativeFairValueOfDerivativeLiability
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeFairValueOfDerivativeNet

us-gaap:DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue
dei:LegalEntity, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeLiabilities

us-gaap:DerivativeLiabilitiesCurrent

us-gaap:DerivativeLiabilitiesNoncurrent
dei:LegalEntity, us-gaap:HedgingDesignation
us-gaap:DerivativeLiabilityCollateralRightToReclaimCashOffset
dei:LegalEntity
us-gaap:DueFromAffiliateCurrent
dei:LegalEntity
us-gaap:DueToAffiliateCurrent

us-gaap:DueToAffiliateNoncurrent

us-gaap:EnergyMarketingAccountsPayable

us-gaap:EnergyMarketingContractLiabilitiesCurrent

us-gaap:EnergyMarketingContractLiabilitiesNoncurrent

us-gaap:EnergyMarketingContractsAssetsCurrent

us-gaap:EnergyMarketingContractsAssetsNoncurrent
dei:LegalEntity
us-gaap:EnergyRelatedInventoryNaturalGasInStorage
dei:LegalEntity, us-gaap:FairValueByAssetClass
us-gaap:FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FinancialLiabilitiesFairValueDisclosure
dei:LegalEntity
us-gaap:GuaranteeObligationsCurrentCarryingValue

us-gaap:GuaranteeObligationsMaximumExposure

us-gaap:InterestPayableCurrent
us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve
us-gaap:InventoryRawMaterials

us-gaap:InventoryRawMaterialsAndSuppliesNetOfReserves
dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:InvestmentsFairValueDisclosure

us-gaap:LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent
dei:LegalEntity
us-gaap:LiabilityForAsbestosAndEnvironmentalClaimsGross
dei:LegalEntity
us-gaap:LimitedLiabilityCompanyLlcMembersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent

us-gaap:LongTermDebtNoncurrent

us-gaap:MarginDepositAssets
dei:LegalEntity
us-gaap:MembersCapital
dei:LegalEntity
us-gaap:MembersEquity
dei:LegalEntity
us-gaap:MembersEquityAttributableToNoncontrollingInterest

us-gaap:MinorityInterest
dei:LegalEntity
us-gaap:NotesPayableRelatedPartiesNoncurrent

us-gaap:OtherAssetsCurrent

us-gaap:OtherCommitment

us-gaap:OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent

us-gaap:OtherReceivables
dei:LegalEntity
us-gaap:PayablesToCustomers
dei:LegalEntity
us-gaap:PrepaidTaxes

us-gaap:PublicUtilitiesAmountOfAllowanceForEarningsOnEquityCapitalizedForRateMakingPurposes

us-gaap:RegulatoryAssetsCurrent

us-gaap:RegulatoryAssetsNoncurrent

us-gaap:RegulatoryLiabilityCurrent

us-gaap:RegulatoryLiabilityNoncurrent

us-gaap:RestrictedCashAndCashEquivalentsAtCarryingValue

us-gaap:RestrictedCashAndCashEquivalentsNoncurrent
dei:LegalEntity
us-gaap:RetainedEarningsAppropriated

us-gaap:RevenueRemainingPerformanceObligation

us-gaap:SharesIssued

us-gaap:ShortTermBorrowings
dei:LegalEntity, us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtWeightedAverageInterestRate
dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:ShorttermDebtFairValue

us-gaap:SpentNuclearFuelObligationNoncurrent

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:TreasuryStockShares

us-gaap:TreasuryStockValue

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate

us-gaap:VariableInterestEntityConsolidatedAssetsCurrent

us-gaap:VariableInterestEntityConsolidatedAssetsNoncurrent

us-gaap:VariableInterestEntityConsolidatedCarryingAmountAssets

us-gaap:VariableInterestEntityConsolidatedCarryingAmountLiabilities

us-gaap:VariableInterestEntityConsolidatedLiabilitiesCurrent

us-gaap:VariableInterestEntityConsolidatedLiabilitiesNoRecourse

us-gaap:VariableInterestEntityConsolidatedLiabilitiesNoncurrent

us-gaap:VariableInterestEntityEntityMaximumLossExposureAmount

us-gaap:VariableInterestEntityNonconsolidatedCarryingAmountAssets

us-gaap:VariableInterestEntityNonconsolidatedCarryingAmountLiabilities

Common Stock Value

us-gaap:CommonStockValue



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value19238192091917119116190631900818973189641886218860188071879418756187221868618676186471675516731167091667916651167511674116716166931665216632165941655916512910790779054903290068923
bPercentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Par Or Stated Value Per Share

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value974974972970969968967965936930928927926925924915866867868863864861860860860855857857856707666665664664663663662662662662661661
bPercentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value973972971968967966964962934928925925924923921913863862861861860858856857856855854854853705664663663662662662661661660660659659
bPercentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-03-312015-12-312015-06-302015-03-312014-12-312014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312011-01-312010-12-312009-12-31
Value972972970968967965965963960960926924858919861861859893858857856856855854854853852663663663662661661659
bPercentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.790.50.930.160.760.560.611.940.860.091.070.220.530.290.190.340.690.740.80.021.150.610.10.60.860.57-0.010.440.350.340.280.910.910.931.010.791.280.671.130.881.151.01.08
bPercentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.790.50.930.160.760.560.61.930.850.091.070.220.530.290.190.330.690.740.80.021.150.60.10.590.860.57-0.010.440.350.330.280.910.90.931.010.791.270.671.130.881.140.991.08
bPercentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value8929768994778814940380769693838187697623875778759002691075736702740165148830725569126024723761636502614160826284656559544686399152954587505244945291439844614116433941414722
bPercentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value419274273254406265310271370270275275421270291291386285334
bPercentage of Revenues4.73.62.92.94.33.33.23.24.23.53.13.54.73.93.84.35.24.43.8
aPercentage of Revenues3.84.45.24.33.83.94.73.53.13.54.23.23.23.34.32.92.93.64.7

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value70364997679973166297781373867495181281268092974672562810367616976531054794737653880703720616696673745674976
bPercentage of Revenues7.98.410.39.17.88.210.19.78.48.810.910.39.09.812.311.19.89.611.710.510.110.814.612.911.310.614.511.211.010.314.916.914.114.719.3
aPercentage of Revenues19.314.714.116.914.910.311.011.214.510.611.312.914.610.810.110.511.79.69.811.112.39.89.010.310.98.88.49.710.18.27.89.110.38.47.9

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value1583135114081373159813981512130915711357129812231497128612491196137611481185107912221128113410681156108011601290148412811388136217841444146613721918149914151357147513891553
bPercentage of Revenues17.717.614.915.617.017.315.615.617.917.814.815.516.618.616.517.818.617.613.414.917.718.715.717.317.817.619.120.522.621.529.634.133.731.529.030.536.334.131.733.034.033.532.9
aPercentage of Revenues32.933.534.033.031.734.136.330.529.031.533.734.129.621.522.620.519.117.617.817.315.718.717.714.913.417.618.617.816.518.616.615.514.817.817.915.615.617.317.015.614.917.617.7

exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value319287380331328289384330327282362303331281362296314271421
bPercentage of Revenues3.63.74.03.83.53.64.03.93.73.74.13.83.74.14.84.44.24.24.8
aPercentage of Revenues4.84.24.24.44.84.13.73.84.13.73.73.94.03.63.53.84.03.73.6

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value477442105296506952784579551246544751124174488843885035358947394294476842325840386480244123789439037724255407035333928401737532739216128622546273925962655235324212278244523782601
bPercentage of Revenues53.554.855.957.556.156.756.955.554.20.255.855.755.951.962.664.164.465.066.15.363.862.960.761.265.466.358.162.561.263.058.554.154.155.554.257.850.253.554.355.356.357.455.1
aPercentage of Revenues55.157.456.355.354.353.550.257.854.255.554.154.158.563.061.262.558.166.365.461.260.762.963.866.20.066.165.064.464.162.651.955.955.755.854.80.054.255.556.956.756.157.555.954.853.5

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value778655900765757653866729715630796701788664841645740661985750693656993805728672895790806715875778946842115312991496126914551266132712041514
bPercentage of Revenues8.78.59.58.78.18.18.98.78.28.39.18.98.89.611.19.610.010.111.210.310.010.913.713.111.210.914.712.612.312.018.719.517.918.422.828.928.328.932.630.830.629.132.1
aPercentage of Revenues32.129.130.630.832.628.928.328.922.818.417.919.518.712.012.312.614.710.911.213.113.710.910.010.311.210.110.09.611.19.68.88.99.18.38.28.78.98.18.18.79.58.58.7

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value13801091122811171361107612511121131010741175
bPercentage of Revenues15.514.213.012.714.513.312.913.414.914.113.4
aPercentage of Revenues13.414.114.913.412.913.314.512.713.014.215.5

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value642531575531628523557510604514530491635509551488592504545
bPercentage of Revenues7.26.96.16.06.76.55.76.16.96.76.16.27.17.47.37.38.07.76.2
aPercentage of Revenues6.27.78.07.37.37.47.16.26.16.76.96.15.76.56.76.06.16.97.2

dei:LegalEntity, us-gaap:ConsolidationItems

exc:PepcoHoldingsLLC, us-gaap:IntersegmentElimination



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-106-109-104-109-113-2-3-5-4
bPercentage of Revenues-1.1-1.2-1.1-1.3-1.2-0.0-0.0-0.1-0.0
aPercentage of Revenues-0.0-0.1-0.0-0.0-1.2-1.3-1.1-1.2-1.1

dei:LegalEntity, us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

exc:PepcoHoldingsLLC, us-gaap:CorporateNonSegment, us-gaap:CorporateAndOther



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value10610910310811315121312
bPercentage of Revenues1.11.21.11.31.20.20.10.20.1
aPercentage of Revenues0.10.20.10.21.21.31.11.21.1

dei:LegalEntity, us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

exc:AtlanticCityElectricCompany, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value20-1-1-2-1036
bPercentage of Revenues0.00.0-0.0-0.0-0.0-0.00.00.00.1
aPercentage of Revenues0.10.00.0-0.0-0.0-0.0-0.00.00.0

exc:AtlanticCityElectricCompany, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value271255407266312272370267269
bPercentage of Revenues2.92.94.33.33.23.24.23.53.1
aPercentage of Revenues3.13.54.23.23.23.34.32.92.9

exc:BaltimoreGasAndElectricCompany, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value161-1-1-725403540
bPercentage of Revenues0.20.0-0.0-0.0-0.10.30.50.50.5
aPercentage of Revenues0.50.50.50.3-0.1-0.0-0.00.00.2

exc:BaltimoreGasAndElectricCompany, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value960799732663984788698639911
bPercentage of Revenues10.19.17.88.210.29.48.08.410.4
aPercentage of Revenues10.48.48.09.410.28.27.89.110.1

exc:CommonwealthEdisonCo, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-245-8-10142242622
bPercentage of Revenues-0.30.1-0.1-0.10.10.00.30.30.3
aPercentage of Revenues0.30.30.30.00.1-0.1-0.10.1-0.3

exc:CommonwealthEdisonCo, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value143213691606140814981307154713311276
bPercentage of Revenues15.115.517.117.415.515.617.617.514.6
aPercentage of Revenues14.617.517.615.615.517.417.115.515.1

exc:DelmarvaPowerandLightCompany, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value20161-20110
bPercentage of Revenues0.00.00.00.10.0-0.00.00.00.1
aPercentage of Revenues0.10.00.0-0.00.00.10.00.00.0

exc:DelmarvaPowerandLightCompany, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value378331327283383331327281352
bPercentage of Revenues4.03.83.53.54.03.93.73.74.0
aPercentage of Revenues4.03.73.73.94.03.53.53.84.0

exc:PecoEnergyCo, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-2-64723333
bPercentage of Revenues-0.0-0.10.00.10.00.00.00.00.0
aPercentage of Revenues0.00.00.00.00.00.10.0-0.1-0.0

exc:PecoEnergyCo, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value902769753646864726712627793
bPercentage of Revenues9.58.78.08.08.98.78.18.29.1
aPercentage of Revenues9.18.28.18.78.98.08.08.79.5

exc:PepcoHoldingsLLC, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value20-4-2-31914162243
bPercentage of Revenues0.2-0.0-0.0-0.00.20.20.20.30.5
aPercentage of Revenues0.50.30.20.20.2-0.0-0.0-0.00.2

exc:PepcoHoldingsLLC, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value120811211363107912321108129410521132
bPercentage of Revenues12.712.714.513.412.713.214.813.812.9
aPercentage of Revenues12.913.814.813.212.713.414.512.712.7

exc:PotomacElectricPowerCompany, exc:OtherRegulatedRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value16-4-2-82035716
bPercentage of Revenues0.2-0.0-0.0-0.10.20.00.10.10.2
aPercentage of Revenues0.20.10.10.00.2-0.1-0.0-0.00.2

exc:PotomacElectricPowerCompany, us-gaap:RegulatedOperation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value559535630531537506599507514
bPercentage of Revenues5.96.16.76.65.56.06.86.75.9
aPercentage of Revenues5.96.76.86.05.56.66.76.15.9

us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-09-302015-06-30
Value-763-751-786-858-780-779-876-758-762-735-77000
bPercentage of Revenues-8.5-9.8-8.3-9.7-8.3-9.6-9.0-9.0-8.7-9.6-8.80.00.0
aPercentage of Revenues0.00.0-8.8-9.6-8.7-9.0-9.0-9.6-8.3-9.7-8.3-9.8-8.5

us-gaap:OperatingSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value89297689947788159403807696938387876876658747
bPercentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.1100.0100.699.9
aPercentage of Revenues99.9100.6100.0100.1100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments

us-gaap:CorporateNonSegment, exc:ContractswithCustomers, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value112108120125130125134156207179206
bPercentage of Revenues1.31.41.31.41.41.51.41.92.42.32.4
aPercentage of Revenues2.42.32.41.91.41.51.41.41.31.41.3

us-gaap:CorporateNonSegment, exc:Other, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value8351-40-1561026-86-8542-15244
bPercentage of Revenues0.90.7-0.4-1.80.10.3-0.9-1.00.5-2.00.5
aPercentage of Revenues0.5-2.00.5-1.0-0.90.30.1-1.8-0.40.70.9

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationErcot



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value288178130102156165149121164186168
bPercentage of Revenues3.22.31.41.21.72.01.51.41.92.41.9
aPercentage of Revenues1.92.41.91.41.52.01.71.21.42.33.2

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationMidAtlantic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value13511162128612701397122013551263139713681494
bPercentage of Revenues15.115.113.614.414.915.114.015.115.917.917.1
aPercentage of Revenues17.117.915.915.114.015.114.914.413.615.115.1

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationMidwest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value105297410551095109510621273975982986980
bPercentage of Revenues11.812.711.112.411.613.213.111.611.212.911.2
aPercentage of Revenues11.212.911.211.613.113.211.612.411.112.711.8

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationNaturalGas



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value160177584508200295522421226244768
bPercentage of Revenues1.82.36.25.82.13.75.45.02.63.28.8
aPercentage of Revenues8.83.22.65.05.43.72.15.86.22.31.8

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationNewYork



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value414373409418475392439444454405303
bPercentage of Revenues4.64.94.34.75.14.94.55.35.25.33.5
aPercentage of Revenues3.55.35.25.34.54.95.14.74.34.94.6

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationOtherRegions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value8738141165157293210210155167142128
bPercentage of Revenues9.810.612.31.83.12.62.21.81.91.91.5
aPercentage of Revenues1.51.91.91.82.22.63.11.812.310.69.8

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationReportableSegmentsTotal



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value39783501404537594082360041513467366835493662
bPercentage of Revenues44.645.542.742.643.444.642.841.441.846.641.8
aPercentage of Revenues41.846.641.841.442.844.643.442.642.745.544.6

us-gaap:OperatingSegments, exc:ContractswithCustomers, exc:GenerationTotalConsolidatedGroup



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value42503786474943924412402048074044410139724636
bPercentage of Revenues47.649.250.149.846.949.849.648.346.852.152.9
aPercentage of Revenues52.952.146.848.349.649.846.949.850.149.247.6

us-gaap:OperatingSegments, exc:Other, exc:GenerationErcot



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value72477910128911159881446124
bPercentage of Revenues0.80.60.81.13.11.40.61.01.60.80.3
aPercentage of Revenues0.30.81.61.00.61.43.11.10.80.60.8

us-gaap:OperatingSegments, exc:Other, exc:GenerationMidAtlantic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1021-24425258804524-12-65
bPercentage of Revenues0.10.3-0.30.50.60.70.80.50.3-0.2-0.7
aPercentage of Revenues-0.7-0.20.30.50.80.70.60.5-0.30.30.1

us-gaap:OperatingSegments, exc:Other, exc:GenerationMidwest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value4768592126737173677271
bPercentage of Revenues0.50.90.60.20.30.90.70.90.80.90.8
aPercentage of Revenues0.80.90.80.90.70.90.30.20.60.90.5

us-gaap:OperatingSegments, exc:Other, exc:GenerationNaturalGas



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value105156295371197194433347234186150
bPercentage of Revenues1.22.03.14.22.12.44.54.12.72.41.7
aPercentage of Revenues1.72.42.74.14.52.42.14.23.12.01.2

us-gaap:OperatingSegments, exc:Other, exc:GenerationNewYork



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1517-161-6-2-29-1-21-13-3
bPercentage of Revenues0.20.2-0.20.0-0.1-0.0-0.3-0.0-0.2-0.2-0.0
aPercentage of Revenues-0.0-0.2-0.2-0.0-0.3-0.0-0.10.0-0.20.20.2

us-gaap:OperatingSegments, exc:Other, exc:GenerationOtherRegions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1926419419926511310911418112661
bPercentage of Revenues2.20.82.02.32.81.41.11.42.11.70.7
aPercentage of Revenues0.71.72.11.41.11.42.82.32.00.82.2

us-gaap:OperatingSegments, exc:Other, exc:GenerationReportableSegmentsTotal



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value33621729246265933935835137321048
bPercentage of Revenues3.82.83.15.27.04.23.74.24.32.80.5
aPercentage of Revenues0.52.84.34.23.74.27.05.23.12.83.8

us-gaap:OperatingSegments, exc:Other, exc:GenerationTotalConsolidatedGroup



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value524424547677866559705613649244242
bPercentage of Revenues5.95.55.87.79.26.97.37.37.43.22.8
aPercentage of Revenues2.83.27.47.37.36.99.27.75.85.55.9

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CorporateNonSegment, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value19515980-31140151488397094551168675713-661044710469569
bPercentage of Revenues2.22.10.8-0.41.51.90.510.08.16.013.38.67.9-1.013.810.66.38.7
aPercentage of Revenues8.76.310.613.8-1.07.98.613.36.08.110.00.51.91.5-0.40.82.12.2

us-gaap:CorporateNonSegment, us-gaap:CorporateAndOther



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value474484455550458487451515446449419
bPercentage of Revenues5.36.34.86.24.96.04.76.15.15.94.8
aPercentage of Revenues4.85.95.16.14.76.04.96.24.86.35.3

us-gaap:OperatingSegments, exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value419274273255406265310271370270275
bPercentage of Revenues4.73.62.92.94.33.33.23.24.23.53.1
aPercentage of Revenues3.13.54.23.23.23.34.32.92.93.64.7

us-gaap:OperatingSegments, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value70364997680073166297781373867495172562810367616976531054
bPercentage of Revenues7.98.410.39.17.88.210.19.78.48.810.99.89.611.710.510.110.814.6
aPercentage of Revenues14.610.810.110.511.79.69.810.98.88.49.710.18.27.89.110.38.47.9

us-gaap:OperatingSegments, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value158313511408137415981398151213091571135712981376114811851080122211281134
bPercentage of Revenues17.717.614.915.617.017.315.615.617.917.814.818.617.613.414.917.718.715.7
aPercentage of Revenues15.718.717.714.913.417.618.614.817.817.915.615.617.317.015.614.917.617.7

us-gaap:OperatingSegments, exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value319287380331328289384329327282362
bPercentage of Revenues3.63.74.03.83.53.64.03.93.73.74.1
aPercentage of Revenues4.13.73.73.94.03.63.53.84.03.73.6

us-gaap:OperatingSegments, exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value477442105296506952784579551246574750421648784768423258404802441237894390
bPercentage of Revenues53.554.855.957.556.156.756.955.654.255.355.764.465.066.166.263.862.960.7
aPercentage of Revenues60.762.963.866.266.165.064.455.755.354.255.656.956.756.157.555.954.853.5

us-gaap:OperatingSegments, exc:GenerationErcot



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value360225209203445276208209308247192172289207163172317194182195303198243
bPercentage of Revenues4.02.92.22.34.73.42.12.53.53.22.22.23.23.02.22.64.33.02.12.74.43.33.4
aPercentage of Revenues3.43.34.42.72.13.04.32.62.23.03.22.22.23.23.52.52.13.44.72.32.22.94.0

us-gaap:OperatingSegments, exc:GenerationMidAtlantic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value13611183126213121449127814351308142113561429143618131432153214991622133615171267128512721441
bPercentage of Revenues15.215.413.314.915.415.814.815.616.217.816.318.220.120.720.222.421.920.517.217.518.621.119.9
aPercentage of Revenues19.921.118.617.517.220.521.922.420.220.720.118.216.317.816.215.614.815.815.414.913.315.415.2

us-gaap:OperatingSegments, exc:GenerationMidwest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value1099104211141116112111351344104810491058105110721163107610891082115012051275116510629811258
bPercentage of Revenues12.313.611.812.711.914.113.912.512.013.912.013.612.915.614.416.115.518.514.416.115.416.317.4
aPercentage of Revenues17.416.315.416.114.418.515.516.114.415.612.913.612.013.912.012.513.914.111.912.711.813.612.3

us-gaap:OperatingSegments, exc:GenerationNaturalGas



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value265333879879397489955768460430918
bPercentage of Revenues3.04.39.310.04.26.19.99.25.25.610.5
aPercentage of Revenues10.55.65.29.29.96.14.210.09.34.33.0

us-gaap:OperatingSegments, exc:GenerationNewYork



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value429390393419469390410440434352310292331356218210254222310229230194190
bPercentage of Revenues4.85.14.14.85.04.84.25.24.94.63.53.73.75.22.93.13.43.43.53.23.33.22.6
aPercentage of Revenues2.63.23.33.23.53.43.43.12.95.23.73.73.54.64.95.24.24.85.04.84.15.14.8

us-gaap:OperatingSegments, exc:GenerationOtherRegions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value10658781359356558323319269348268189241271232222291383294212292381314334
bPercentage of Revenues11.911.414.34.05.94.03.33.24.03.52.23.13.03.42.94.35.24.52.44.05.55.24.6
aPercentage of Revenues4.65.25.54.02.44.55.24.32.93.43.03.12.23.54.03.23.34.05.94.014.311.411.9

us-gaap:OperatingSegments, exc:GenerationReportableSegmentsTotal



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value43143718433742214741393945093815404237193720371343223655369537284245361743543537353331704011
bPercentage of Revenues48.348.445.847.950.448.846.545.546.148.842.547.148.052.948.855.657.455.549.348.851.152.655.4
aPercentage of Revenues55.452.651.148.849.355.557.455.648.852.948.047.142.548.846.145.546.548.850.447.945.848.448.3

us-gaap:OperatingSegments, exc:GenerationTotalConsolidatedGroup



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value4774421052965069527845795512465447514174488843885035358947394294476842325840
bPercentage of Revenues53.554.855.957.556.156.756.955.554.254.855.855.755.951.962.664.164.465.066.1
aPercentage of Revenues66.165.064.464.162.651.955.955.755.854.854.255.556.956.756.157.555.954.853.5

us-gaap:OperatingSegments, exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value778655900763757653866729715630796740661985751693656993
bPercentage of Revenues8.78.59.58.78.18.18.98.78.28.39.110.010.111.210.410.010.913.7
aPercentage of Revenues13.710.910.010.411.210.110.09.18.38.28.78.98.18.18.79.58.58.7

us-gaap:OperatingSegments, exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value13801091122811171361107612511122131010741175
bPercentage of Revenues15.514.213.012.714.513.312.913.414.914.113.4
aPercentage of Revenues13.414.114.913.412.913.314.512.713.014.215.5

us-gaap:OperatingSegments, exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value642531575531628523557509604514530
bPercentage of Revenues7.26.96.16.06.76.55.76.16.96.76.1
aPercentage of Revenues6.16.76.96.15.76.56.76.06.16.97.2

us-gaap:StatementBusinessSegments

exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-31
Value19515980-30140151488397234731181703764-37106574352361414881266881620382608629852-21559-24219
bPercentage of Revenues2.22.10.8-0.31.51.90.510.08.26.213.58.98.5-0.514.111.17.19.416.917.512.710.35.39.99.713.9-0.38.9-0.44.7
aPercentage of Revenues4.7-0.48.9-0.313.99.79.95.310.312.717.516.99.47.111.114.1-0.58.58.913.56.28.210.00.51.91.5-0.30.82.12.2

exc:GenerationErcot



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value365229212203444277209209314247191172295207163170316192180194302197243182427315293291533
bPercentage of Revenues4.13.02.22.34.73.42.22.53.63.22.22.23.33.02.22.54.32.92.02.74.43.33.43.06.65.14.84.68.1
aPercentage of Revenues8.14.64.85.16.63.03.43.34.42.72.02.94.32.52.23.03.32.22.23.23.62.52.23.44.72.32.23.04.1

exc:GenerationMidAtlantic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value13641189125613081456128214401318143213651425144318001416152014091632134615131275128912771418126113911229132312931417
bPercentage of Revenues15.315.513.314.815.515.914.915.716.317.916.318.320.020.520.121.022.120.717.117.618.621.219.620.521.420.021.820.621.6
aPercentage of Revenues21.620.621.820.021.420.519.621.218.617.617.120.722.121.020.120.520.018.316.317.916.315.714.915.915.514.813.315.515.3

exc:GenerationMidwest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value108210341108111311171130134610401038105010531069116410831095107711511206127611621061981127099910131071118812051200
bPercentage of Revenues12.113.411.712.611.914.013.912.411.813.812.013.612.915.714.516.115.618.514.516.015.416.317.516.215.617.419.519.218.3
aPercentage of Revenues18.319.219.517.415.616.217.516.315.416.014.518.515.616.114.515.712.913.612.013.811.812.413.914.011.912.611.713.412.1

exc:GenerationNaturalGas



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value299348894836440526980769480449930
bPercentage of Revenues3.34.59.49.54.76.510.19.25.55.910.6
aPercentage of Revenues10.65.95.59.210.16.54.79.59.44.53.3

exc:GenerationNewYork



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value429390393418469392409437428347307283323346203207250218310230232194187187184174169210185
bPercentage of Revenues4.85.14.14.75.04.94.25.24.94.63.53.63.65.02.73.13.43.33.53.23.43.22.63.02.82.82.83.32.8
aPercentage of Revenues2.83.32.82.82.83.02.63.23.43.23.53.33.43.12.75.03.63.63.54.64.95.24.24.95.04.74.15.14.8

exc:GenerationOtherRegions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value10408611353406513287288270335259184221238223223222376289214286375308341231271240225104329
bPercentage of Revenues11.611.214.34.65.53.63.03.23.83.42.12.82.63.22.93.35.14.42.43.95.45.14.73.74.23.93.71.75.0
aPercentage of Revenues5.01.73.73.94.23.74.75.15.43.92.44.45.13.32.93.22.62.82.13.43.83.23.03.65.54.614.311.211.6

exc:GenerationReportableSegmentsTotal



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value42803703432242634698390244843815402837013707368542713626367435514245361843523536353131694008316436263218360133394055
bPercentage of Revenues47.948.245.648.450.048.346.345.545.948.642.346.847.452.548.553.057.455.549.348.751.152.655.451.355.852.459.253.161.8
aPercentage of Revenues61.853.159.252.455.851.355.452.651.148.749.355.557.453.048.552.547.446.842.348.645.945.546.348.350.048.445.648.247.9

exc:GenerationTotalConsolidatedGroup



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value4774421052965069527845795512465447514174488843885035358947394294476842325840480244123789439037724255407035333898403137652743
bPercentage of Revenues53.554.855.957.556.156.756.955.554.254.855.855.755.951.962.664.164.465.066.166.263.862.960.761.265.466.358.162.061.463.258.5
aPercentage of Revenues58.563.261.462.058.166.365.461.260.762.963.866.266.165.064.464.162.651.955.955.755.854.854.255.556.956.756.157.555.954.853.5

Operating Expenses

us-gaap:OperatingExpenses



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value7559688182628107825271388648
bPercentage of OperatingExpenses100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues89.288.487.892.087.289.584.7

us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-759-744-783-874-790-790-886
bPercentage of OperatingExpenses-10.0-10.8-9.5-10.8-9.6-11.1-10.2
aPercentage of Revenues-9.1-9.8-8.4-9.9-8.3-9.7-8.5

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CorporateNonSegment, us-gaap:CorporateAndOther



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value457484459534459492444
bPercentage of OperatingExpenses6.07.05.66.65.66.95.1
aPercentage of Revenues4.66.14.96.14.86.35.1

us-gaap:OperatingSegments, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value612569756691628578800
bPercentage of OperatingExpenses8.18.39.28.57.68.19.3
aPercentage of Revenues8.37.26.77.88.07.46.9

us-gaap:OperatingSegments, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1256104011351131127511111223
bPercentage of OperatingExpenses16.615.113.714.015.515.614.1
aPercentage of Revenues12.613.813.612.812.013.514.1

us-gaap:OperatingSegments, exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4274409649635035496142985218
bPercentage of OperatingExpenses56.559.560.162.160.160.260.3
aPercentage of Revenues53.853.252.857.152.453.347.9

us-gaap:OperatingSegments, exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value595510678599603526724
bPercentage of OperatingExpenses7.97.48.27.47.37.48.4
aPercentage of Revenues7.56.56.46.87.26.66.7

us-gaap:OperatingSegments, exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1124926105499111169231125
bPercentage of OperatingExpenses14.913.512.812.213.512.913.0
aPercentage of Revenues11.611.411.911.211.112.012.6

us-gaap:OperatingSegments, exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value515438491465516438501
bPercentage of OperatingExpenses6.86.45.95.76.36.15.8
aPercentage of Revenues5.25.45.55.35.25.75.8

Operating Income Loss

us-gaap:OperatingIncomeLoss



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value1353841121870811469421101125814752321296714126764748370712001134136670514008291638891254100550870460371435910621181103412029391367101814021076140310161255
bPercentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues26.624.532.326.131.423.125.820.923.822.522.326.67.712.09.211.28.416.419.314.42.313.820.39.715.517.416.210.56.49.414.19.114.83.016.815.011.411.712.28.012.910.915.2

dei:LegalEntity

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value7928211484252328792525268319-12129512529
bPercentage of OperatingIncomeLoss5.83.31.72.07.32.72.12.25.410.81.93.66.62.9-25.14.14.22.22.1
aPercentage of Revenues0.30.40.70.4-1.60.30.90.30.30.30.90.30.20.30.90.20.20.40.9

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value9180220109103851771631249822819011559187144110992041131025516910111469163613052-11842354153
bPercentage of OperatingIncomeLoss6.79.518.115.49.09.016.113.08.442.217.626.69.19.138.720.49.28.714.916.07.36.6103.711.49.16.932.18.75.07.3-3.17.91.95.212.7
aPercentage of Revenues3.01.20.42.1-0.20.90.51.02.71.11.81.62.30.91.51.62.31.51.52.12.50.91.32.42.61.31.41.91.81.11.11.22.31.01.0

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value328311276242323288292286404319314217389324274217327243230197287258238236278232209300218142226285243254200229280256291224203209206
bPercentage of OperatingIncomeLoss24.237.022.734.228.230.626.522.727.4137.524.230.430.750.156.730.727.221.416.827.920.531.1146.026.522.223.141.142.636.219.963.026.820.624.616.624.420.525.120.820.814.520.616.4
aPercentage of Revenues4.45.04.75.46.55.85.35.14.05.54.67.14.82.43.34.83.43.84.33.83.34.34.22.72.63.74.43.23.64.74.32.83.64.24.63.43.03.63.42.72.94.03.7

exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value5144724851424952594178207230-7246322463
bPercentage of OperatingIncomeLoss3.85.25.96.84.54.54.54.14.017.76.02.85.74.6-14.96.52.72.14.6
aPercentage of Revenues0.70.40.40.7-1.00.40.80.30.90.50.70.60.50.50.50.50.80.60.6

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value48214733335311282347501500-46738794342-13415230622703719249887429-389405721603-642901743842726737546478016608835879167111046676862
bPercentage of OperatingIncomeLoss35.617.527.34.927.129.931.539.833.9-201.329.913.227.0-2.085.932.551.862.052.635.363.451.7-238.745.657.560.0-12.641.228.953.875.863.463.862.666.670.364.657.765.366.174.666.568.7
aPercentage of Revenues18.316.324.117.320.513.316.714.715.914.114.216.95.86.42.74.6-1.19.811.16.6-5.47.112.83.48.110.88.43.45.5-0.23.81.24.4-6.15.76.03.63.53.30.43.51.95.4

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value18314522216515412714215716913719215020415219612815412422315513313414917015513820311717815117713115316121070215182194160172154210
bPercentage of OperatingIncomeLoss13.517.218.223.313.413.512.912.511.559.114.821.016.123.540.618.112.810.916.322.09.516.291.419.112.413.740.016.629.521.149.312.313.015.617.57.515.717.913.814.912.315.216.7
aPercentage of Revenues4.43.74.03.94.34.14.11.64.23.52.93.33.82.52.71.93.32.22.42.82.12.21.92.12.51.92.11.92.62.22.31.92.21.81.91.91.51.61.61.92.31.92.0

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value256165175126245153126159285148180
bPercentage of OperatingIncomeLoss18.919.614.417.821.416.211.412.619.363.813.9
aPercentage of Revenues2.11.93.31.91.31.92.61.41.82.12.9

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value12793846511285568714984795113297-1051231158363
bPercentage of OperatingIncomeLoss9.411.16.99.29.89.05.16.910.136.26.17.110.415.0-21.717.49.67.34.6
aPercentage of Revenues0.71.31.61.8-1.41.41.50.60.91.11.71.00.61.11.20.70.91.21.4

Interest Expense

us-gaap:InterestExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value403403397410387367365359377426363347506366277268243145335333247228217224228246617225240250189175176176175177169269177
bPercentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues4.06.13.23.93.53.83.34.44.04.23.73.610.14.03.53.63.03.83.64.63.82.23.34.03.75.35.64.44.15.64.34.33.84.54.14.74.25.24.5

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3129292827252526242223232420202121202121222323122932333435344132323233
bPercentage of InterestExpense7.77.27.36.87.06.86.87.26.45.26.36.64.75.57.27.88.613.86.36.38.910.110.65.412.713.05.315.114.613.621.718.318.218.218.9
aPercentage of Revenues0.70.70.60.80.90.60.50.50.50.50.40.20.30.40.30.30.20.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.40.3

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value878684838282868386988284194888381807881777876777371723507371717984828282837913081
bPercentage of InterestExpense21.621.321.220.221.222.323.623.122.823.022.624.238.324.030.030.232.953.824.223.131.633.335.532.631.129.356.732.429.628.441.848.046.646.646.946.946.748.345.8
aPercentage of Revenues1.83.01.51.81.61.81.52.11.71.21.11.25.81.21.11.21.11.31.11.10.91.21.11.21.11.32.21.10.91.31.01.00.91.00.90.90.91.11.0

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value101107102118939391881031209082678987865690907977747341829382788585544237454544373735
bPercentage of InterestExpense25.126.625.728.824.025.324.924.527.328.224.823.613.224.331.432.123.062.126.923.731.232.533.618.336.037.813.334.735.434.028.624.021.025.625.724.921.913.819.8
aPercentage of Revenues0.80.80.71.00.91.00.71.11.21.41.31.21.31.51.30.71.01.21.11.11.01.40.81.31.11.30.71.01.01.61.21.00.91.21.01.31.11.41.1

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value303030302828303128282828272828272525252526252526262526262928282931313130357442
bPercentage of InterestExpense7.47.47.67.37.27.68.28.67.46.67.78.15.37.710.110.110.317.27.57.510.511.011.511.611.410.24.211.612.111.214.816.617.617.617.716.920.727.523.7
aPercentage of Revenues0.91.70.70.70.60.70.60.70.60.50.40.40.40.40.40.40.30.40.40.30.30.40.30.40.40.40.30.40.30.40.30.40.30.30.30.30.30.40.3

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6667656865656362625962
bPercentage of InterestExpense16.416.616.416.616.817.717.317.316.413.817.1
aPercentage of Revenues0.70.80.70.70.60.80.70.80.70.90.7

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value33343432323231323128292930313732313130
bPercentage of InterestExpense8.28.48.67.88.38.78.58.98.26.68.08.45.98.513.411.912.821.49.0
aPercentage of Revenues0.30.50.40.50.50.40.30.40.30.40.40.40.30.40.30.40.40.40.4

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value158212467-32419444-2833123720528336120144114133-244-1780-247354243103162155-1717293101-43194148-14310093134206-12293
bPercentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues2.1-2.83.93.01.82.2-2.73.74.1-0.71.51.52.8-0.32.42.61.44.05.1-3.40.9-0.3-3.32.01.52.11.30.53.22.72.73.9-0.30.52.1-3.74.92.81.8

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value81081274885447-8034745334558765275345164410383
bPercentage of OtherNonoperatingIncomeExpense5.14.71.7-3.73.69.1-28.62.42.12.01.419.4-66.72.13.55.3-1.6-29.43.8-1.21.12.14.94.94.5-35.32.929.05.0-7.02.13.4-11.24.04.37.51.5-6.63.2
aPercentage of Revenues0.10.20.10.20.10.10.30.10.10.10.10.40.10.10.10.10.10.10.10.00.00.10.10.10.10.0-0.90.10.00.10.10.10.10.00.10.10.10.10.1

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value128171430-34217929-44300209181259618511793133-257-3194-25534222890139134-331285483-76178134-1647675119192-13379
bPercentage of OtherNonoperatingIncomeExpense81.080.792.1105.692.365.9157.190.688.288.391.516.7154.281.281.6100.0105.3182.4117.5103.296.693.887.485.886.5194.174.458.182.2176.791.890.5114.776.080.688.893.2109.084.9
aPercentage of Revenues1.8-3.03.62.61.51.7-3.13.43.8-1.31.30.92.1-0.52.12.31.23.84.9-3.51.1-0.5-3.52.01.21.72.10.13.02.42.43.6-0.50.41.9-3.94.52.21.4

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-251-19764-740-199-329-399-35-149-231-90-321-396-232-173-145-497-172-265-590965-124-84-79-269-451-138-145-299-1-34-325-82-88-4931-397-90
bPercentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues-2.0-9.00.6-1.1-1.7-1.8-6.1-0.9-0.0-5.0-2.2-2.2-7.4-4.4-1.2-1.4-1.70.11.4-8.1-3.0-2.6-6.7-2.2-2.3-3.4-4.4-4.1-1.0-3.0-1.7-0.4-4.1-4.1-2.1-8.40.7-2.6-2.8

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-83-79-79-74-78-81-81-78-84-97-81-80-277-88-82-77-79-76-81-77-77-75-75-68-67-70-348-50-69-71-78-83-70-82-81-76-79-126-81
bPercentage of NonoperatingIncomeExpense33.140.1-123.410.039.224.620.3222.956.442.090.024.969.937.947.453.115.944.230.613.1-80.2-1500.060.581.084.826.077.236.247.623.77800.0244.121.5100.092.0155.1-254.831.790.0
aPercentage of Revenues-1.8-2.9-1.5-1.7-1.6-1.8-1.3-2.1-1.7-1.2-1.1-0.8-5.7-1.1-1.0-1.1-1.0-1.2-1.1-1.1-0.9-1.2-1.1-1.1-1.1-1.3-3.1-1.0-0.9-1.3-1.0-0.9-0.8-1.0-0.8-0.8-0.8-1.0-0.9

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1955319-46978-73-1452029652159-8510818-437-325-130-8-35025314253952-12646-24-2-16112491-201313075155-17044
bPercentage of NonoperatingIncomeExpense-7.6-27.9498.463.4-39.222.236.3-577.1-64.4-22.5-176.726.5-27.3-7.82.3-25.565.475.63.059.3263.52840.0-4.0-46.4-65.846.8-10.217.41.453.8-12400.0-267.661.8-37.8-34.1-153.1500.042.8-48.9
aPercentage of Revenues1.0-3.92.91.70.60.7-3.82.32.6-2.7-0.0-0.40.8-2.10.80.60.12.43.7-4.8-0.1-2.0-4.40.6-0.10.31.2-1.11.80.71.12.4-1.5-0.90.8-5.33.40.70.2

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-29-30-29-29-30-32-31-30-29-29-29-29-28-29-29-28-27-27-26-26-27-27-26-27-28-28-26-27-30-29-29-29-31-31-28-31-35-78-41
bPercentage of NonoperatingIncomeExpense11.615.2-45.33.915.19.77.885.719.512.632.29.07.112.516.819.35.415.79.84.4-28.1-540.021.032.135.410.45.819.620.79.72900.085.39.537.831.863.3-112.919.645.6
aPercentage of Revenues-0.9-1.8-0.7-0.7-0.6-0.7-0.6-0.7-0.6-0.5-0.5-0.4-0.4-0.5-0.4-0.4-0.4-0.4-0.4-0.4-0.3-0.4-0.4-0.4-0.4-0.4-0.3-0.4-0.3-0.4-0.3-0.4-0.3-0.4-0.3-0.3-0.3-0.4-0.3

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-53-53-53-58-54-54-52-48-49-46-49
bPercentage of NonoperatingIncomeExpense21.126.9-82.87.827.116.413.0137.132.919.954.4
aPercentage of Revenues-0.6-0.6-0.6-0.6-0.5-0.7-0.6-0.7-0.6-0.7-0.6

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value172144310261376659-720452-7221513634010218426811532736320422277-5431143923956182161126158423255332446367552176563
bPercentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues12.64.010.48.28.87.24.810.63.42.12.52.90.93.96.85.0-0.74.66.10.34.15.01.64.02.41.53.81.72.5-0.95.2-8.60.60.81.50.33.31.91.9

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value121136151813286740318065366664835327437311458273616551409-1620-31247
bPercentage of IncomeTaxExpenseBenefit7.07.611.657.713.119.747.5-9.38.8-43.137.247.810.65.935.917.930.49.820.4185.07.35.1-107.48.78.26.798.27.70.07.1-10.14.7-1.23.610.5
aPercentage of Revenues0.90.3-0.10.5-0.30.20.00.20.90.30.60.40.80.20.40.50.80.50.50.70.90.10.40.80.90.40.50.80.30.20.20.20.40.10.1

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value454640285243468913110492577591775499685947847265598566-589059296181615850627912194
bPercentage of IncomeTaxExpenseBenefit26.231.912.9107.738.065.278.0-12.429.0-144.442.841.922.189.241.820.186.120.816.3235.019.926.0-120.419.019.427.6-103.649.536.623.038.619.123.917.511.216.914.368.816.7
aPercentage of Revenues2.12.81.51.41.01.31.22.01.30.50.91.4-1.01.11.31.00.91.21.20.60.71.01.30.81.01.30.80.71.11.41.51.10.50.50.60.30.40.60.5

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8778224-21878239-1584240-158127-3173-31151131-36181226-83291199-199179288149-1127855823031816723533631143335399
bPercentage of IncomeTaxExpenseBenefit50.654.272.3-838.556.934.815.3220.053.1219.459.1-2.250.9-30.482.148.9-31.355.462.3-415.069.071.8368.557.665.662.3-1.869.852.846.0145.675.265.570.875.384.778.419.970.9
aPercentage of Revenues8.90.88.26.96.75.13.28.04.91.01.32.0-0.02.44.42.9-2.73.34.2-1.12.62.8-0.52.02.0-0.41.9-0.01.5-2.12.7-18.90.10.30.8-2.52.41.01.0

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value14132511-2-1-2202820362854234321372758322523344035325592542512717475618532952
bPercentage of IncomeTaxExpenseBenefit8.19.08.142.3-1.5-1.5-3.4-2.86.2-27.816.720.615.922.523.47.832.28.316.0160.05.98.3-63.012.98.013.498.24.915.533.332.36.46.714.212.64.99.616.59.2
aPercentage of Revenues1.20.71.00.41.11.00.30.71.10.70.40.10.90.50.50.60.50.40.40.40.70.40.50.30.60.30.60.40.40.30.30.2-0.0-0.0-0.00.10.30.20.2

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1465741591088336-9
bPercentage of IncomeTaxExpenseBenefit8.14.21.626.92.922.715.3-15.018.4-50.0-4.2
aPercentage of Revenues-0.10.50.91.30.10.20.00.10.10.10.2

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value5226-272483820073523-2540321812
bPercentage of IncomeTaxExpenseBenefit2.91.40.623.1-1.510.63.4-6.78.4-27.80.05.110.322.5-13.614.927.85.53.3
aPercentage of Revenues0.10.30.40.6-0.30.30.40.10.00.30.40.60.00.1-0.00.10.00.00.1

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value12113615181328
bPercentage of IncomeTaxExpenseBenefit7.07.611.657.713.119.747.5
aPercentage of Revenues0.30.20.20.20.40.10.1

us-gaap:OperatingSegments, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value45464028524346
bPercentage of IncomeTaxExpenseBenefit26.231.912.9107.738.065.278.0
aPercentage of Revenues0.50.50.60.30.40.60.5

us-gaap:OperatingSegments, exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value8778224-21878239
bPercentage of IncomeTaxExpenseBenefit50.654.272.3-838.556.934.815.3
aPercentage of Revenues0.10.30.8-2.52.41.01.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value79950689026785582656197386811598546562337151263619683749-67210636889711157484979522205175451696570509694-711096611143
bPercentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues25.61.420.7-1.613.711.110.817.49.62.93.10.41.68.111.518.11.311.415.4-9.38.510.58.43.92.04.96.20.611.21.59.923.56.87.28.30.39.46.68.9

dei:LegalEntity

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value257108365-1842361791422214309-249436-5327528256129319396468-65823217-206236453194-121-100-65-98420796261189425-18897-1631112
bPercentage of ComprehensiveIncomeNetOfTax32.221.341.0-707.730.130.821.6112.235.6-216.544.3-115.248.98.3169.549.051.558.062.59.777.431.5-212.421.260.639.0-127.4-454.5-31.7-56.093.1114.445.837.161.225.481.8-267.297.3
aPercentage of Revenues24.9-3.717.0-0.48.44.14.919.99.0-1.6-1.0-1.6-2.03.27.03.8-2.83.611.9-0.95.36.14.31.93.40.43.1-0.75.0-3.33.526.41.52.22.5-2.13.91.42.9

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value189106117621878465315366140
bPercentage of ComprehensiveIncomeNetOfTax23.720.913.1238.523.814.49.90.217.657.414.2
aPercentage of Revenues1.60.91.70.00.71.02.00.71.21.42.1

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-9958-48674526743-16-16493139-50-19-42-5
bPercentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues-0.1-0.6-0.3-0.70.60.30.6-0.2-0.20.50.80.50.00.7-0.50.60.1-0.1

dei:LegalEntity

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-06-30
Value-10958-48664516543-16-16493036-53-8
bPercentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest111.1100.0100.0100.098.5100.098.197.0100.0100.0100.0100.096.892.3106.0160.0
aPercentage of Revenues-0.1-0.70.50.30.6-0.2-0.20.50.80.50.00.7-0.50.60.1-0.1

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value790515948-22852586708204091199969137531298151263661688
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues10.68.93.92.04.35.91.711.11.310.424.37.37.39.1-0.210.06.78.8

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value55451607163511287662451251115431101865144
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest7.08.716.9-322.77.48.718.13.76.845.512.981.010.210.466.932.77.76.4
aPercentage of Revenues0.70.71.31.30.40.61.41.40.60.70.91.30.60.70.81.70.60.6

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value2001861571411931641651201891181418137145115
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest25.336.116.6-640.922.728.023.35.920.7119.214.659.17.048.776.2
aPercentage of Revenues1.52.10.41.01.61.52.21.41.72.02.11.61.72.42.2

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value247117423-2323021831932279352-26542022245-8256119364404
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest31.322.744.61054.535.431.227.3111.738.6-267.743.316.146.1-2.7169.545.255.158.7
aPercentage of Revenues6.24.91.83.4-0.12.70.34.8-3.54.027.22.02.33.2-2.64.51.52.8

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value140102168124126961131071128812792122100124
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest17.719.817.7-563.614.816.416.05.212.388.913.167.223.033.682.1
aPercentage of Revenues1.61.41.41.21.51.21.31.31.21.21.31.41.81.31.6

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value9864553689543117874358227949-108
bPercentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest12.412.45.8-163.610.49.24.40.89.543.46.016.114.916.4-71.5
aPercentage of Revenues-1.40.70.90.30.70.61.00.20.30.70.90.40.60.81.1

Net Income Loss

dei:LegalEntity

us-gaap:NetIncomeLoss

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value257108363-1782341781362224305-250423-42236-831013787165166446386443495424605382561425657512528
bPercentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues11.212.415.110.312.68.711.49.49.89.77.311.23.52.81.32.24.1-0.12.6-0.54.8-3.33.526.51.42.22.5-2.03.81.42.9

Assets

us-gaap:Assets



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value12273812159612159311966611948511724911701811670011847311710411706811490411453511277811174295384951289221387391868148526483656794687992479661784207824378554783537743477628550925415651986513765224049180
bPercentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value1030410006996797169541924191959104892387868821870488578325836182958134801781308078791578777958786176577968763974997504720073697205
bPercentage of Assets8.48.28.28.18.07.97.97.87.57.57.57.67.77.47.58.78.68.79.39.39.39.410.09.89.610.29.89.59.69.39.513.1
aPercentage of Assets13.19.59.39.69.59.810.29.69.810.09.49.39.39.38.78.68.77.57.47.77.67.57.57.57.87.97.98.08.18.28.28.4

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value32326318893158231213311193044630002297262964929160287562833528020281052688726532261292596125731253922484524544242942411823686233492325622905224712258522589226532298322348223192165220697
bPercentage of Assets26.326.226.026.126.026.025.625.525.024.924.624.724.524.924.127.827.528.229.429.229.129.330.630.229.729.829.729.228.729.229.141.142.443.043.441.442.1
aPercentage of Assets42.141.443.443.042.441.129.129.228.729.229.729.829.730.230.629.329.129.229.428.227.527.824.124.924.524.724.624.925.025.525.626.026.026.126.026.226.3

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value47984484024868247556482074766848375483874774448130486094697447568468974700246529464794512545318453484501944422410804123240498396783999140681410904108741723274332608625633256602453422406
bPercentage of Assets39.139.840.039.740.340.741.341.540.341.141.540.941.541.642.148.848.948.951.952.252.853.151.751.650.850.651.151.852.453.153.749.848.249.349.947.045.6
aPercentage of Assets45.647.049.949.348.249.853.753.152.451.851.150.650.851.651.753.152.852.251.948.948.948.842.141.641.540.941.541.140.341.541.340.740.339.740.039.839.1

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value113791100210956106421062110345102181017011480110411093210831110411058610462103671007210126101699943100519761976696179745940794919353966192049215915693368996891089859019
bPercentage of Assets9.39.09.08.98.98.88.78.79.79.49.39.49.69.49.410.910.611.011.611.511.811.712.312.012.212.012.111.912.311.911.916.617.217.317.317.218.3
aPercentage of Assets18.317.217.317.317.216.611.911.912.311.912.112.012.212.012.311.711.811.511.611.010.610.99.49.49.69.49.39.49.78.78.78.88.98.99.09.09.3

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2257622454222942198421957217662137521247
bPercentage of Assets18.418.518.318.418.418.618.318.2
aPercentage of Assets18.218.318.618.418.418.318.518.4

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value8603855684208299819981237896783277757648741773357219709968776908
bPercentage of Assets7.07.06.96.96.96.96.76.76.66.56.36.46.36.36.27.2
aPercentage of Assets7.26.26.36.36.46.36.56.66.76.76.96.96.96.97.07.0

dei:LegalEntity, us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

exc:PepcoHoldingsLLC, us-gaap:CorporateNonSegment, us-gaap:CorporateAndOther



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value109091081910763107131051410600
bPercentage of Assets9.09.09.09.19.09.1
aPercentage of Assets9.19.09.19.09.09.0

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value95159634976895759688952494778342905988178415817281908235813079498118811977031695
bPercentage of Assets7.88.18.28.28.38.28.07.17.77.77.37.27.38.68.58.69.39.49.02.1
aPercentage of Assets2.19.09.49.38.68.58.67.37.27.37.77.77.18.08.28.38.28.28.17.8

us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value-10085-10299-10213-9800-10378-10655-10980-10552-11286-11986-11768-11334-11897-12125-11653-11728-11741-11221
bPercentage of Assets-8.2-8.5-8.4-8.2-8.7-9.1-9.4-9.0-9.5-10.2-10.1-9.9-10.4-10.8-10.4-12.3-13.5-14.0
aPercentage of Assets-14.0-13.5-12.3-10.4-10.8-10.4-9.9-10.1-10.2-9.5-9.0-9.4-9.1-8.7-8.2-8.4-8.5-8.2

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CorporateNonSegment, us-gaap:CorporateAndOther



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value825481428325835584188438883386181066210783107001036915389
bPercentage of Assets6.76.76.87.07.07.27.57.49.09.29.19.016.1
aPercentage of Assets16.19.09.19.29.07.47.57.27.07.06.86.76.7

us-gaap:OperatingSegments, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-31
Value103041000699679716954192419195910489238786882187048857832583618295813480178130807880787861
bPercentage of Assets8.48.28.28.18.07.97.97.87.57.57.57.67.77.47.58.78.68.79.39.310.29.8
aPercentage of Assets9.810.29.39.38.78.68.77.57.47.77.67.57.57.57.87.97.98.08.18.28.28.4

us-gaap:OperatingSegments, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-31
Value32326318893158231213311193044630002297262964929160287562833528020281052688726532261292596125731253922539224118
bPercentage of Assets26.326.226.026.126.026.025.625.525.024.924.624.724.524.924.127.827.528.229.429.232.030.2
aPercentage of Assets30.232.029.229.428.227.527.824.124.924.524.724.624.925.025.525.626.026.026.126.026.226.3

us-gaap:OperatingSegments, exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-31
Value47984484024868247556482074766848375483874774448130486094697447568468974700246529464794512545318453484534841232
bPercentage of Assets39.139.840.039.740.340.741.341.540.341.141.540.941.541.642.148.848.948.951.952.257.151.6
aPercentage of Assets51.657.152.251.948.948.948.842.141.641.540.941.541.140.341.541.340.740.339.740.039.839.1

us-gaap:OperatingSegments, exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-31
Value11379110021095610642106211034510218101701148011041109321083111041105861046210367100721012610169994399439617
bPercentage of Assets9.39.09.08.98.98.88.78.79.79.49.39.49.69.49.410.910.611.011.611.512.512.0
aPercentage of Assets12.012.511.511.611.010.610.99.49.49.69.49.39.49.78.78.78.88.98.99.09.09.3

us-gaap:OperatingSegments, exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2257622454222942198421957217662137521247
bPercentage of Assets18.418.518.318.418.418.618.318.2
aPercentage of Assets18.218.318.618.418.418.318.518.4

us-gaap:OperatingSegments, exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value86038556842082998199812378967832
bPercentage of Assets7.07.06.96.96.96.96.76.7
aPercentage of Assets6.76.76.96.96.96.97.07.0

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-04-012013-12-31
Value97879526954696679804961297279565952083859148889385148240831082688190798981828160777360001755
bPercentage of Assets8.07.87.98.18.28.28.38.28.07.27.87.77.47.37.48.78.68.79.49.49.10.02.2
aPercentage of Assets2.20.09.19.49.48.78.68.77.47.37.47.77.87.28.08.28.38.28.28.17.97.88.0

Liabilities

us-gaap:Liabilities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value88386876898788986596860978441084453845688815687814887778729287049854568453768062678396714462753626816021459427566905698457594568325683056737561635502555439406173971037784373553859036453
bPercentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets74.173.972.772.773.373.771.471.171.772.272.672.572.371.371.371.070.672.271.872.871.371.475.775.876.076.075.875.074.472.572.272.072.172.472.372.172.0

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value67546558650963626297602659785963591558685897585661005395541754185289519053075325521452225318530651495510520451415161485351014904
bPercentage of Liabilities7.67.57.47.37.37.17.17.16.76.76.66.77.06.36.48.07.87.78.58.58.78.89.49.38.99.79.29.19.28.89.212.1
aPercentage of Assets8.96.66.36.66.56.77.06.56.66.76.26.16.16.15.65.65.74.84.85.35.15.05.05.05.15.15.15.35.35.45.45.5

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value21729214292124220966210122057920296201842020520180198951961019410196671858018289180291796717793174851704016846167041659016213159481589715582152961549015530156161600315405154151474213815
bPercentage of Liabilities24.624.424.224.224.424.424.023.922.923.022.422.522.323.022.026.926.626.828.427.928.328.329.529.128.228.128.027.527.228.228.038.440.340.841.338.237.9
aPercentage of Assets28.128.230.029.629.528.320.020.019.519.820.320.320.420.821.020.120.020.120.419.519.019.216.617.416.917.117.017.217.117.317.317.617.617.517.517.617.7

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value32391328103298632048322473172932417324833394735000350453371833829335303364933559335553246932150312973069330772285722849027947274812772128016281602758227834187251806317841180581735715614
bPercentage of Liabilities36.637.437.537.037.537.638.438.438.539.939.538.638.939.239.849.349.548.451.249.951.051.850.450.048.548.448.849.450.150.150.246.145.547.248.345.042.8
aPercentage of Assets31.733.235.134.333.434.035.935.635.935.735.435.035.135.636.036.836.036.136.835.235.335.230.129.729.529.329.929.928.727.827.727.127.026.827.127.026.4

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value7243694769136822693768106815659379387555746274167649726571717131684569356979682269476683669265526726639863846284659661756180613163056002592660156367
bPercentage of Liabilities8.27.97.97.98.18.18.17.89.08.68.48.58.88.58.510.510.110.311.110.911.511.211.811.511.711.311.211.111.711.211.115.115.915.915.915.617.5
aPercentage of Assets12.911.511.511.511.611.18.08.08.48.08.28.28.48.28.48.08.17.98.07.57.27.56.46.46.76.56.46.56.75.65.85.85.85.75.75.75.9

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1302812882130041270212791126661255612422
bPercentage of Liabilities14.714.714.814.714.915.014.914.7
aPercentage of Assets10.610.710.810.710.610.710.610.6

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value5690564056355559553554705357529952595144508950354897482047844668
bPercentage of Liabilities6.46.46.46.46.46.56.36.36.05.95.75.85.65.65.76.9
aPercentage of Assets4.94.34.34.34.44.34.44.44.54.64.74.64.64.64.64.6

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1227381215961215931196661194851172491170181167001184731171041170681149041145351127781117429538495128922138739186814852648365679468799247855477628550925415651986513765224049180
bPercentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312012-03-312011-12-31
Value1030410006996797169541924191959104892387868821870488578325829573697205
bPercentage of LiabilitiesAndStockholdersEquity8.48.28.28.18.07.97.97.87.57.57.57.67.77.48.79.513.1
aPercentage of Assets13.19.58.77.47.77.67.57.57.57.87.97.98.08.18.28.28.4

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value32326318893158231213311193044630002297262964929160287562833528020281052688726532261292596125731253922484524544242942411823686233492325622905224712258522589226532298322348223192165220697
bPercentage of LiabilitiesAndStockholdersEquity26.326.226.026.126.026.025.625.525.024.924.624.724.524.924.127.827.528.229.429.229.129.330.630.20.00.00.029.20.00.029.141.142.443.043.441.442.1
aPercentage of Assets42.141.443.443.042.441.129.129.228.729.229.729.829.730.230.629.329.129.229.428.227.527.824.124.924.524.724.624.925.025.525.626.026.026.126.026.226.3

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value479844840248682475564820747668483754838747744481304860946974475684689746529
bPercentage of LiabilitiesAndStockholdersEquity39.139.840.039.740.340.741.341.540.341.141.540.941.541.648.8
aPercentage of Assets48.841.641.540.941.541.140.341.541.340.740.339.740.039.839.1

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value113791100210956106421062110345102181017011480110411093210831110411058610462103671007210126101699943100519761976696179745940794919353966192049215915693368996891089859019
bPercentage of LiabilitiesAndStockholdersEquity9.39.09.08.98.98.88.78.79.79.49.39.49.69.49.410.910.611.011.611.511.811.712.312.00.00.00.011.90.00.011.916.617.217.317.317.218.3
aPercentage of Assets18.317.217.317.317.216.611.911.912.311.912.112.012.212.012.311.711.811.511.611.010.610.99.49.49.69.49.39.49.78.78.78.88.98.99.09.09.3

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2257622454222942198421957217662137521247
bPercentage of LiabilitiesAndStockholdersEquity18.418.518.318.418.418.618.318.2
aPercentage of Assets18.218.318.618.418.418.318.518.4

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value8603855684208299819981237896783277757648741773357219709968776908
bPercentage of LiabilitiesAndStockholdersEquity7.07.06.96.96.96.96.76.76.66.56.36.46.36.36.27.2
aPercentage of Assets7.26.26.36.36.46.36.56.66.76.76.96.96.96.97.07.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value32023315483135730764310203051530231298572810027546265302583726027257562571725793257702350623065226082359522853225682273221859213532108921431218212203321816143851435614112139311356012640
bPercentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets25.726.027.127.126.526.128.128.527.827.327.027.227.428.428.427.327.726.026.425.527.127.023.022.822.722.522.723.523.725.625.826.026.025.725.825.926.1

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value35503448345833543244321532173141300829182924284827572740275426872655263726332563251124652450236523182268224521682153215720782111
bPercentage of StockholdersEquity11.110.911.010.910.510.510.610.510.710.611.011.010.610.610.710.410.311.211.411.310.610.810.910.410.610.610.610.19.99.89.514.7
aPercentage of Assets3.82.72.82.72.82.92.92.93.03.12.92.93.03.02.92.82.82.52.42.42.52.52.52.52.72.72.72.72.82.82.82.9

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value10597104601034010247101079867970695429444898088618725861084388307824381007994793879077805769875907528747374017359732371757095705970376980694369046910688267356528
bPercentage of StockholdersEquity33.133.233.033.332.632.332.132.033.632.633.433.833.132.832.332.031.434.034.435.033.133.733.633.134.234.734.934.232.932.232.448.948.649.249.651.054.40.00.0
aPercentage of Assets0.00.014.013.213.413.412.912.89.19.29.29.39.49.49.49.49.69.29.29.19.18.78.58.67.47.57.57.67.67.78.08.28.38.48.58.68.58.68.6

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value413640554043382036843535340335773542348634703415339233213291323632273191319031213104307830743065301930093020298229782942294829382944290728972883256521822023
bPercentage of StockholdersEquity12.912.912.912.411.911.611.312.012.612.713.113.213.012.912.812.512.513.613.813.813.213.513.613.513.814.114.313.913.613.413.520.420.520.620.821.320.30.00.0
aPercentage of Assets0.00.05.25.55.65.65.45.33.83.83.83.83.93.83.83.83.93.73.63.63.73.53.43.42.92.93.03.03.03.03.03.12.93.03.13.23.33.33.4

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value291329162785274026642653253925332516250423282300232222792093224020871922
bPercentage of StockholdersEquity9.19.28.98.98.68.78.48.59.09.18.88.98.98.88.18.79.28.5
aPercentage of Assets2.42.42.31.92.02.02.02.02.12.12.22.22.32.22.32.32.42.4

dei:LegalEntity, us-gaap:StatementEquityComponents

exc:BaltimoreGasAndElectricCompany, us-gaap:CommonStock



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-312009-12-31
Value1714171416231605160516051498142114211421138813811381136713601360136013601360136013601360136013601360136013601294129412941294
bPercentage of StockholdersEquity5.55.65.25.35.35.45.35.25.45.55.35.45.45.35.85.96.05.86.06.06.06.26.46.46.36.26.25.99.09.510.2
aPercentage of Assets2.62.52.31.71.81.71.71.71.71.71.71.71.61.61.61.61.51.41.21.21.21.21.21.21.31.41.41.41.41.41.4

exc:BaltimoreGasAndElectricCompany, us-gaap:RetainedEarnings



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value174416401621161016121536151014971503142713691359137313201277127312031151110510901005958908885808793797784817
bPercentage of StockholdersEquity5.65.35.25.35.35.15.45.45.75.55.35.35.35.15.45.55.34.94.84.84.44.44.34.23.83.63.63.65.7
aPercentage of Assets1.51.01.01.01.01.11.21.21.31.41.31.31.41.51.41.41.21.21.21.21.31.31.31.31.41.41.41.41.4

exc:CommonwealthEdisonCo, us-gaap:OtherAdditionalCapital



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value738573227209704769356822673863576250615060225795571756775516548454685362530452305190518951885186501450165016501250034992499249924992499049824968
bPercentage of StockholdersEquity23.623.823.223.122.922.824.023.123.623.823.122.522.222.023.523.824.222.723.223.222.823.724.324.623.423.022.823.034.834.835.435.836.839.50.00.0
aPercentage of Assets0.00.010.19.69.79.69.29.16.56.56.46.46.66.66.56.56.66.36.36.36.36.06.05.15.15.35.45.35.45.75.85.96.06.06.16.1

exc:CommonwealthEdisonCo, us-gaap:RetainedEarningsAppropriated



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value300629762949287128222771275726742662262626392694264126172529250524902494244524112389233522642305236022102130209820862040200319641970194318091610
bPercentage of StockholdersEquity9.69.79.59.49.39.39.89.710.010.210.110.510.310.110.810.911.010.610.710.710.510.710.610.911.010.19.79.614.514.214.214.114.515.40.00.0
aPercentage of Assets0.00.04.03.83.83.93.83.82.72.82.83.02.92.92.93.03.02.92.92.92.92.72.72.42.42.32.32.32.32.32.42.42.42.52.52.5

exc:CommonwealthEdisonCo, us-gaap:RetainedEarningsUnappropriated



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1720-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639-1639
bPercentage of StockholdersEquity-5.2-5.3-5.3-5.4-5.4-5.5-5.8-6.0-6.2-6.3-6.3-6.4-6.4-6.4-7.0-7.1-7.2-6.9-7.2-7.3-7.2-7.5-7.7-8.2-7.6-7.5-7.4-7.5-11.4-11.4-11.6-11.8-12.1-13.00.00.0
aPercentage of Assets0.00.0-3.3-3.1-3.2-3.2-3.0-3.0-2.1-2.1-2.1-2.1-2.2-2.1-2.1-2.1-2.1-2.0-1.9-1.9-1.9-1.8-1.7-1.5-1.5-1.4-1.4-1.4-1.4-1.4-1.4-1.4-1.4-1.4-1.4-1.3

exc:PecoEnergyCo, us-gaap:CommonStock



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-312009-12-31
Value2723257825602530248924892489247324732473247324552455245524392439243924392415241524152388238823882388237923612318
bPercentage of StockholdersEquity8.78.48.38.38.28.38.99.09.39.69.59.59.59.510.410.610.810.310.610.710.610.911.211.311.116.517.418.3
aPercentage of Assets4.74.54.33.03.13.03.03.03.02.92.92.82.82.62.62.22.22.22.22.12.12.12.12.12.22.12.22.2

exc:PotomacElectricPowerCompany, us-gaap:CommonStock



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value165016361555155514701470147014701309130913091309112211221010930
bPercentage of StockholdersEquity5.35.35.05.14.94.95.25.34.95.15.05.14.44.44.54.1
aPercentage of Assets1.21.21.21.01.21.11.11.11.31.21.31.31.31.31.41.4

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:CommonStock, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value18181714171417141623160516051605
bPercentage of StockholdersEquity5.75.45.55.65.25.35.35.4
aPercentage of Assets1.41.41.41.41.41.41.41.5

us-gaap:CommonStock, exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value2752272327232578256025302489248923792379237923792379236123612361231822912255
bPercentage of StockholdersEquity8.68.68.78.48.38.38.28.310.910.810.916.516.616.716.917.418.30.00.0
aPercentage of Assets0.00.04.74.54.64.54.44.33.13.13.02.12.12.22.12.22.22.22.2

us-gaap:CommonStock, exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value17651765165016361555155514701470
bPercentage of StockholdersEquity5.55.65.35.35.05.14.94.9
aPercentage of Assets1.31.31.31.31.41.41.51.4

us-gaap:OtherAdditionalCapital, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value75097446738573227209704769356822
bPercentage of StockholdersEquity23.423.623.623.823.223.122.922.8
aPercentage of Assets5.85.96.06.06.16.16.16.1

us-gaap:RetainedEarnings, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value17321734174416401621161016121536
bPercentage of StockholdersEquity5.45.55.65.35.25.35.35.1
aPercentage of Assets1.31.41.41.41.41.41.41.4

us-gaap:RetainedEarningsAppropriated, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value31393065300629762949287128222771
bPercentage of StockholdersEquity9.89.79.69.79.59.49.39.3
aPercentage of Assets2.42.42.42.52.52.52.52.6

Assets Current

us-gaap:AssetsCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value122061165512476133601347311489115331183412724122321219412412122081149511364153341686715425113571209711837982396751013799519409927410133113281175411815548962874987465963985441
bPercentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets11.112.29.19.611.610.015.215.214.512.911.912.012.512.712.211.713.913.913.016.717.716.110.210.210.710.810.410.410.710.19.99.811.311.210.39.69.9

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value7516147537867986587558117026808128421114714819845822776962957869916106710119621314105897310788281066968
bPercentage of AssetsCurrent6.25.36.05.95.95.76.56.95.55.66.76.89.16.27.25.54.95.08.57.97.39.311.010.09.714.011.49.69.57.09.017.6
aPercentage of Assets1.81.41.11.41.21.41.71.21.31.31.11.01.11.10.80.90.90.70.61.00.70.70.60.60.70.60.60.70.70.60.50.6

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1606148215071570168514801336136414011576144615541634217413721518142216161637172314801434141715401495151115381775162419471948210627521901179521511579
bPercentage of AssetsCurrent13.212.712.111.812.512.911.611.511.012.911.912.513.418.912.19.98.410.514.414.212.514.614.615.215.016.116.617.514.316.616.538.443.838.138.533.629.0
aPercentage of Assets3.24.13.53.75.13.82.52.52.12.32.01.91.91.91.81.71.72.01.91.81.51.61.21.91.41.41.21.31.21.21.11.31.41.31.21.21.3

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value7159737677218433804965676884682064396594651465286135572561716342705064436719763874585727618964395805530752626211715880858241320427792676268830873360
bPercentage of AssetsCurrent58.763.361.963.159.757.259.757.650.653.953.452.650.349.854.341.441.841.859.263.163.058.364.063.558.356.456.761.363.268.869.858.444.253.757.748.261.8
aPercentage of Assets6.85.95.25.15.15.810.610.49.17.96.76.87.38.17.86.88.78.87.77.07.46.65.55.15.45.75.65.65.45.85.95.66.77.06.36.15.8

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value8436588167828137157368229166566787571121801816842683740849714982803934906121099411241094153011911211121615241404138016701006
bPercentage of AssetsCurrent6.95.66.55.96.06.26.46.97.25.45.66.19.27.07.25.54.04.87.55.98.38.29.78.912.210.612.110.813.510.110.222.224.228.229.626.118.5
aPercentage of Assets2.03.22.72.72.82.21.61.52.01.41.41.31.51.11.21.01.20.81.00.80.70.90.70.71.00.70.60.60.80.70.60.60.70.70.70.50.7

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value15781546145315331700167214931551
bPercentage of AssetsCurrent12.913.311.611.512.614.612.913.1
aPercentage of Assets1.31.31.41.41.31.21.31.3

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value616906857709782593618473930870801721808854103386811081211991418
bPercentage of AssetsCurrent4.96.86.46.26.85.04.93.97.67.06.66.37.15.66.15.69.810.08.44.1
aPercentage of Assets0.51.21.41.30.91.10.90.70.60.70.80.80.40.50.50.70.60.70.80.5

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value7456266229138677187936036314849839088667558778821085899116012391044457
bPercentage of AssetsCurrent6.15.45.06.86.46.26.95.15.04.08.17.37.16.67.75.86.45.810.210.28.84.5
aPercentage of Assets0.61.21.41.31.01.10.90.80.70.80.80.80.40.50.50.70.60.70.80.50.50.6

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value16837358801349191869478789812035366096351897164796065027265601418251878276313629141609164499177214861700134972110161071562487161227351168252420101271311
bPercentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets0.00.04.10.00.00.03.10.91.12.01.80.91.72.21.91.01.32.12.01.21.63.22.22.16.57.66.80.91.51.70.60.50.51.00.80.70.61.61.10.70.61.4

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-06-302011-03-312010-12-312009-12-31
Value13081271137221729121123341559272441642715233174571158912153157491211505014
bPercentage of CashAndCashEquivalentsAtCarryingValue7.71.11.40.55.91.02.81.92.42.21.83.618.00.30.50.10.40.42.23.41.01.12.51.90.446.114.96.07.13.921.84.821.530.83.10.7
aPercentage of Assets0.00.10.30.20.10.20.10.20.10.10.60.00.00.00.00.00.10.00.00.00.00.00.00.30.00.00.00.00.00.00.00.10.00.00.00.1

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value76656813512430707625739315644736216751511086644384136349330144312919234356942750344140914787
bPercentage of CashAndCashEquivalentsAtCarryingValue4.58.87.710.06.54.38.98.521.47.35.18.82.344.72.21.00.70.85.93.51.62.84.52.22.19.43.99.71.82.12.623.033.216.75.53.11.23.51.64.53.728.0
aPercentage of Assets0.00.00.20.00.00.00.10.10.20.70.40.00.00.00.20.00.10.00.00.10.00.10.10.10.10.10.10.00.70.00.00.00.00.20.10.10.00.10.10.10.10.1

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value10195755377501187420610416360265400290375373377431545456532780131130556612589282222256718309302194961431091734562209848175310991135127
bPercentage of CashAndCashEquivalentsAtCarryingValue60.578.261.055.661.960.577.546.329.949.465.745.719.822.639.36.67.57.629.241.547.422.461.978.256.422.429.145.248.868.930.448.813.419.435.528.380.872.669.554.789.340.8
aPercentage of Assets0.00.02.20.00.00.00.90.30.20.30.90.31.21.10.90.30.31.21.60.70.41.50.90.60.50.60.50.30.30.30.30.30.20.30.40.50.41.00.60.40.50.8

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value2242041130102182127133045286351620313295322638303469398217609563023626482721481945183192495224322072053033934
bPercentage of CashAndCashEquivalentsAtCarryingValue13.32.74.79.65.32.62.730.227.48.44.69.927.212.31.44.50.40.42.11.612.56.810.713.537.05.739.124.438.120.220.519.148.456.851.132.415.817.78.115.13.110.9
aPercentage of Assets0.00.00.60.00.00.01.00.50.61.00.40.20.40.80.50.40.10.80.30.10.10.40.00.00.00.00.30.00.20.50.10.00.00.30.20.00.00.10.10.00.00.2

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value1254143162052801261306819915016013814516433024033439237262
bPercentage of CashAndCashEquivalentsAtCarryingValue14.230.716.529.535.614.010.812.732.723.68.48.415.12.54.54.018.320.913.53.9
aPercentage of Assets0.10.40.50.40.30.30.20.10.10.10.10.20.10.10.10.20.20.30.30.1

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value1681061254143162052801261306819915016013814516433024033439237262
bPercentage of CashAndCashEquivalentsAtCarryingValue10.014.414.230.716.529.535.614.010.812.732.723.68.48.415.12.54.54.018.320.913.53.9
aPercentage of Assets0.10.40.50.40.30.30.20.10.10.10.10.20.10.10.10.20.20.30.30.10.10.1

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4188412545644607423940944190440138543825388641584061367135943187321532273702348228152973299727212584260928352787283528862868161316851766180019321563
bPercentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets3.23.73.53.43.12.93.73.73.63.53.63.33.23.43.83.63.34.04.23.53.43.33.23.33.53.63.33.33.33.83.63.53.53.83.83.43.4

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value242278385353296300394375288312393395332289328300318360489390366419580480404415476401358324419428
bPercentage of AccountsReceivableNetCurrent5.86.78.47.77.07.39.48.57.58.210.19.58.27.99.19.49.911.213.211.213.014.119.417.615.615.916.814.412.611.214.626.5
aPercentage of Assets0.80.50.40.50.50.60.50.50.60.70.50.40.40.60.40.30.30.30.30.30.30.30.30.20.30.30.30.20.30.30.20.2

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value561528539539590579485559496529461528546557479533557522503477486516475451443455495539602675596655697748722768676
bPercentage of AccountsReceivableNetCurrent13.412.811.811.713.914.111.612.712.913.811.912.713.415.213.316.717.316.213.613.717.317.415.816.617.117.417.519.321.223.420.840.641.442.440.139.843.3
aPercentage of Assets1.41.51.41.41.31.20.80.90.80.70.60.60.60.60.60.60.60.50.60.60.60.60.40.50.50.50.40.50.40.50.40.50.50.50.40.40.5

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2587252828002941254524352478265323392242227824332318207619632095205620452320229517051733152114291489146414701482158015791520578592582601469495
bPercentage of AccountsReceivableNetCurrent61.861.361.363.860.059.559.160.360.758.658.658.557.156.654.665.764.063.462.765.960.658.350.852.557.656.151.953.255.754.753.035.835.133.033.424.331.7
aPercentage of Assets1.00.91.21.11.11.02.02.02.01.91.91.91.91.81.92.12.02.62.72.22.22.21.81.82.02.11.91.92.02.32.12.12.12.52.32.12.1

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value286302394321307285349327240258314306271248288258283301390320258304422360250286395364294307333380396435476695392
bPercentage of AccountsReceivableNetCurrent6.87.38.67.07.27.08.37.46.26.78.17.46.76.88.08.18.89.310.59.29.210.214.113.29.711.013.913.110.410.611.623.623.524.626.436.025.1
aPercentage of Assets0.81.30.90.80.70.70.40.40.40.50.50.40.30.50.50.40.30.40.40.30.30.30.30.20.20.30.30.20.20.30.30.20.30.30.30.20.2

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value512489445453500495484486
bPercentage of AccountsReceivableNetCurrent12.211.99.89.811.812.111.611.0
aPercentage of Assets0.40.40.40.40.40.40.40.4

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value258254219225235272246250265256199235292255240230
bPercentage of AccountsReceivableNetCurrent6.26.24.84.95.56.65.95.76.96.75.15.77.26.96.77.2
aPercentage of Assets0.20.20.20.30.20.20.20.20.20.20.20.20.20.20.20.2

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value152146165149154138139106347371264253231219186179296297213260
bPercentage of AccountsReceivableNetCurrent3.33.23.93.63.73.13.62.88.98.96.56.96.46.95.85.58.08.57.69.6
aPercentage of Assets0.30.20.30.30.20.20.20.20.20.20.30.30.10.10.10.10.10.10.10.1

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value163161152146165149154138139106347371264253231219186179296297213260
bPercentage of AccountsReceivableNetCurrent3.93.93.33.23.93.63.73.13.62.88.98.96.56.96.46.95.85.58.08.57.69.6
aPercentage of Assets0.30.20.30.30.20.20.20.20.20.20.30.30.10.10.10.10.10.10.10.10.10.1

Inventory Net

dei:LegalEntity

us-gaap:InventoryNet

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value37343233312529292223
bPercentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets0.00.00.00.00.00.00.00.00.00.0

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value16215115214814614614615215216015415915615515716414814413512512111210710910310210091928884818379767271
bPercentage of InventoryNet437.8444.1475.0448.5471.0584.0503.4524.10.00.00.0722.70.00.00.0713.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
aPercentage of Assets0.10.10.10.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value11811510993818589876367
bPercentage of InventoryNet318.9338.2340.6281.8261.3340.0306.9300.0286.4291.3
aPercentage of Assets0.10.10.10.10.10.10.10.10.10.1

Inventory Raw Materials And Supplies

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value78593780307746076707758407528474711742027306772748726307155571214706936940657439558145393553001520875163051747477424733046495459944578445186439144261342105325703188230856305492994127341
bPercentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets55.657.359.559.458.959.154.255.056.057.558.558.758.459.260.161.960.660.060.658.558.760.262.162.762.262.362.062.161.763.663.864.263.564.163.764.264.0

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value87968612840882438039786477257602741872837166704069046747668465976459637362806204612660305939586457135637556854985378529452115132
bPercentage of PropertyPlantAndEquipmentNet11.211.010.910.710.610.410.310.210.210.09.99.89.79.59.611.511.611.811.811.911.911.712.412.412.312.312.212.212.212.412.415.8
aPercentage of Assets9.36.76.86.97.07.17.27.27.37.57.27.27.17.26.96.86.96.06.06.06.16.16.26.36.56.66.76.76.96.97.17.2

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value22795225272227422058216422132321010207232035320019196921933518811184161797117502170011649316099157931538915121148901466614444142331402013826136111342813267131211295512824126901257812125
bPercentage of PropertyPlantAndEquipmentNet29.028.928.828.828.528.328.127.927.927.527.127.026.426.125.930.530.530.630.430.329.829.231.231.031.130.930.630.631.031.531.540.340.641.641.542.044.3
aPercentage of Assets24.724.124.724.723.923.817.117.317.417.617.918.118.118.318.718.118.018.218.417.917.918.316.116.316.416.816.817.117.217.818.018.218.118.418.318.518.6

exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value3941389338483821374836893620357934803412333432733222317731323070
bPercentage of PropertyPlantAndEquipmentNet5.05.05.05.04.94.94.84.84.84.74.64.64.54.54.55.3
aPercentage of Assets3.22.82.82.82.82.82.92.93.13.13.13.13.23.23.23.2

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2359123810240342398124168244792471424906247932526125893255852637426656261662584324982237662341422945231432374320132201111979719678198131953118708177021748013475130421222412106116629809
bPercentage of PropertyPlantAndEquipmentNet30.030.531.031.331.932.533.133.633.934.735.735.837.037.737.745.044.844.144.244.144.845.942.242.542.642.843.343.242.641.541.541.440.939.639.638.935.9
aPercentage of Assets19.922.323.623.524.124.522.522.923.924.925.325.124.925.225.328.427.126.426.825.826.327.123.423.623.022.322.121.620.921.321.120.920.220.019.819.619.2

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value9100894087668610846183078176805378757758765975657400730372097141702769576867680166486545648063846270620761416078599659605924587457965730567556205297
bPercentage of PropertyPlantAndEquipmentNet11.611.511.311.211.211.010.910.910.810.710.510.610.410.310.412.412.612.913.013.112.912.613.613.513.513.513.413.513.714.014.118.018.218.618.618.819.4
aPercentage of Assets10.810.811.011.010.710.77.67.77.77.77.87.97.98.08.27.87.87.87.97.57.47.56.56.56.56.66.56.66.66.97.07.17.17.27.27.47.4

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1396813788136191344613167129291268812498
bPercentage of PropertyPlantAndEquipmentNet17.817.717.617.517.417.217.016.8
aPercentage of Assets10.710.811.011.011.211.211.311.4

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value6734662365346460633762076095600158665759565955715409532152255162
bPercentage of PropertyPlantAndEquipmentNet8.68.58.48.48.48.28.28.18.07.97.87.87.67.57.59.0
aPercentage of Assets5.44.74.74.74.84.84.95.05.15.25.35.35.45.45.45.5

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value61476145615861576181618662135293542554155139514751415160493248114720463845171171
bPercentage of PropertyPlantAndEquipmentNet7.98.08.18.28.38.38.57.37.57.67.27.37.49.08.88.98.98.98.72.5
aPercentage of Assets1.55.35.35.45.25.25.44.64.64.54.74.64.55.25.35.35.35.25.15.1

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value6079608461476145615861576181618662135293542554155139514751415160493248114720463845171171
bPercentage of PropertyPlantAndEquipmentNet7.77.87.98.08.18.28.38.38.57.37.57.67.27.37.49.08.88.98.98.98.72.5
aPercentage of Assets1.55.35.35.45.25.25.44.64.64.54.74.64.55.25.35.35.35.25.15.15.05.0

Property Plant And Equipment Gross

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value235902426623695229022312222302219052106420591197351971619169183541734016776163751618515553152071474214932143691406613713133661290512579121841189011367-1124410959109191049010411100649023
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets18.319.320.320.220.219.9-14.514.715.215.516.116.516.817.217.717.217.517.017.416.917.017.215.015.416.016.716.816.917.418.018.719.019.419.119.520.019.2

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value377237203670363335793530347134053351335833113254319831613069301629622928290528682825278127412702265826562627259525792549-2508-2465
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment16.015.315.515.915.515.815.816.216.317.016.817.017.418.218.318.418.318.819.119.518.919.419.519.719.920.620.921.321.722.422.3-22.5
aPercentage of Assets-4.5-3.23.33.33.33.43.43.33.43.43.33.33.33.33.23.13.22.72.82.82.82.82.92.82.93.03.03.03.03.03.13.1

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value504649494833468445574491439142694191412240403937384137853716371036143571324734323370332532473184310730352969299829062844-2769275026722592250924282129
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment21.420.420.420.519.720.120.020.320.420.920.520.520.921.822.222.722.323.021.423.322.623.123.123.223.223.523.624.624.425.024.625.124.524.724.124.123.6
aPercentage of Assets4.34.64.95.04.95.0-3.63.73.73.83.83.93.94.04.14.04.04.03.73.93.83.93.33.43.43.43.53.53.53.73.83.83.83.94.04.14.1

exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value1407138013541329131512951273124712311212119511751171115711401139
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment6.05.75.75.85.75.85.85.96.06.16.16.16.46.76.87.0
aPercentage of Assets1.21.01.01.01.01.01.01.01.11.11.11.11.11.11.11.1

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1197212902126631220612753121431193611428111931055010801105621000491798950863986598146790576127868739772457034684865216347601459105526-5563531353945080512048804214
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment50.853.253.453.355.254.454.554.354.453.554.855.154.552.953.452.853.552.452.051.652.751.551.551.351.250.550.549.449.748.649.548.549.448.449.248.546.7
aPercentage of Assets8.69.310.09.810.09.6-7.27.17.57.78.18.38.68.89.18.89.28.89.08.89.19.18.08.18.79.29.29.09.49.810.210.410.710.210.410.69.8

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value367036363598356135213482344534113366333032933253321331853139310130583028298929172972296929582935291428742840279727652731-2691266226242595256325312442
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment15.615.015.215.515.215.615.716.216.316.916.717.017.518.418.718.918.919.519.719.819.920.721.021.421.822.322.623.023.324.023.924.324.024.724.625.127.1
aPercentage of Assets5.04.85.05.04.84.8-3.53.53.53.63.63.73.73.73.73.53.53.43.43.33.23.32.82.82.82.82.82.82.82.92.93.02.93.03.03.03.0

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value3473343133923354331132693224317731713131309030503026299529602929
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment14.714.114.314.614.314.714.715.115.415.915.715.916.517.317.617.9
aPercentage of Assets3.12.62.72.62.72.62.72.72.72.82.82.82.82.82.82.8

dei:LegalEntity, us-gaap:PropertyPlantAndEquipmentByType

exc:ExelonGenerationCoLLC, us-gaap:NuclearFuel



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value3040296932783094326331593303301631713186319829362861
bPercentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment12.813.014.213.914.915.016.015.316.116.617.416.917.5
aPercentage of Assets3.02.62.82.82.72.62.82.72.82.62.72.52.5

Long Term Investments

us-gaap:LongTermInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value47161862062564963664064063463864862959250245563962060756854456283982511651154117111811184838836827751740736725717704
bPercentage of LongTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets1.41.41.41.41.41.41.11.11.11.51.51.51.41.51.01.00.70.60.60.70.70.70.40.40.50.50.60.50.50.50.50.50.50.50.50.50.4

dei:LegalEntity

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value248401404414433423431433429426435418381294250210197183122104154432401400401409411420828270413838353546
bPercentage of LongTermInvestments52.764.965.266.266.766.567.367.767.766.867.166.564.458.654.932.931.830.121.519.127.451.548.634.334.734.934.835.59.89.88.55.55.15.24.84.96.5
aPercentage of Assets0.10.10.10.10.10.10.10.10.10.50.50.50.50.50.50.50.20.10.10.20.20.20.20.30.30.40.40.40.40.40.40.40.40.30.30.30.2

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value135133132130133133132132
bPercentage of LongTermInvestments28.721.521.320.820.520.920.620.6
aPercentage of Assets0.10.10.10.10.10.10.10.1

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value109108106105105105104102102102101102100999968
bPercentage of LongTermInvestments23.117.517.116.816.216.516.215.916.116.015.616.216.919.721.810.6
aPercentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1

Goodwill

us-gaap:Goodwill



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-31
Value66776677667766776677667766776677667766776677667766726696668826722672267226722672267226742625262526252625262526252625262526252625262526252625262526252625
bPercentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets0.05.35.05.15.04.84.83.43.43.43.33.43.33.33.33.33.23.13.13.12.92.82.86.05.95.85.85.75.75.65.75.75.75.65.65.55.55.4

dei:LegalEntity

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-09-302015-12-31
Value40054005400540054005400540054005400540000
bPercentage of Goodwill60.060.060.060.060.060.060.060.060.060.00.0
aPercentage of Assets0.03.53.53.43.43.43.43.33.33.33.3

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value31233038301715751560119413331322127712651440147214741366139814451499138812341160113910929349641121117511401128117611561126912938751766763859
bPercentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Assets1.71.51.51.41.71.71.51.51.51.41.51.51.41.21.21.31.31.31.41.51.61.51.31.21.31.31.21.11.11.11.11.01.31.32.52.52.5

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value351354347395380318259238203237331325332324330324295283276271278275276291300312336299285282291315311311360388411
bPercentage of OtherAssetsNoncurrent11.211.711.525.124.426.619.418.015.918.723.022.122.523.723.622.419.720.422.423.424.425.229.630.226.826.629.526.524.224.425.834.533.241.447.050.947.8
aPercentage of Assets0.80.70.70.60.60.60.40.40.40.40.40.40.40.40.30.30.30.30.30.30.30.30.30.30.30.30.30.20.20.20.20.30.30.30.30.30.3

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value191518411813755730679657662648620648688692632650627881798776731714687651645798829789836877851816577609410399365184
bPercentage of OtherAssetsNoncurrent61.360.660.147.946.856.949.350.150.749.045.046.746.946.346.543.458.857.562.963.062.762.969.766.971.270.669.274.174.673.672.563.364.954.652.147.821.4
aPercentage of Assets0.40.70.80.81.11.01.11.11.11.11.01.11.00.80.80.80.80.80.90.90.90.70.60.60.60.60.60.50.50.60.60.60.60.61.51.51.6

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value30302927343191212111920242120213631323439383538383636404137384642354043315
bPercentage of OtherAssetsNoncurrent1.01.01.01.72.22.60.70.90.90.91.31.41.61.51.41.52.42.22.62.93.43.53.73.93.43.13.23.53.53.23.45.04.54.75.25.636.7
aPercentage of Assets0.60.10.10.10.10.10.00.00.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3563603706067706970
bPercentage of OtherAssetsNoncurrent11.411.812.33.84.35.95.25.3
aPercentage of Assets0.10.10.10.10.10.30.30.3

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value232232230226242243231235314277223133848592827882115106
bPercentage of OtherAssetsNoncurrent7.714.714.718.918.218.418.118.621.818.815.19.76.05.96.15.96.37.110.111.0
aPercentage of Assets0.10.10.10.10.10.10.10.10.10.20.20.30.20.20.20.20.20.20.20.2

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value6922725725825625427027426126735031525716713590100919095132127
bPercentage of OtherAssetsNoncurrent2.27.58.516.416.421.320.320.720.421.124.321.417.412.29.76.26.76.67.38.211.613.2
aPercentage of Assets0.20.20.10.10.10.10.10.10.10.20.30.30.20.20.20.20.20.20.20.20.20.1

Liabilities Current

us-gaap:LiabilitiesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value130851293412229114041014096261015310796123951396514437134571215811894137709118784765267374876284318567735177287507837483217784777080839052498949774268417142404238
bPercentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities11.611.011.211.312.512.316.314.713.813.714.614.713.013.613.014.414.014.011.89.711.613.416.313.914.015.416.315.914.112.812.011.411.813.213.914.714.8

dei:LegalEntity

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value347299492422566789703619345356320320338375444297
bPercentage of LiabilitiesCurrent2.72.34.03.75.68.26.95.72.82.52.22.42.83.23.23.3
aPercentage of Liabilities0.40.50.40.40.40.40.40.40.70.80.90.70.50.60.30.4

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value66586883477470777775776061264069370710031165113811347977007808467577478188276449489599731048607840758
bPercentage of LiabilitiesCurrent5.16.76.86.87.08.17.57.04.94.64.85.38.29.88.312.410.210.710.69.79.08.711.110.78.611.311.512.513.57.59.315.2
aPercentage of Liabilities1.91.51.11.91.71.71.71.11.51.41.31.31.31.21.01.21.71.31.41.20.80.80.70.70.90.90.90.80.90.91.00.8

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2243163215941925175621911945229422463750364529382589267929382766272318441776198621602080181620481947225622361655172319181848194625532408243921341597
bPercentage of LiabilitiesCurrent17.112.613.016.917.322.819.221.218.126.925.221.821.322.521.330.334.728.324.122.725.624.324.726.525.926.926.921.322.223.720.439.051.356.458.550.337.7
aPercentage of Liabilities4.45.56.56.46.44.83.33.53.12.93.94.03.43.63.23.53.63.22.82.74.04.13.53.13.03.44.14.32.52.72.32.62.02.21.81.92.5

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value6344684266605769476735224156418950596064523756834307418747754933478638644275445938354215381538673896410238644097425547265428214419071747207618432262
bPercentage of LiabilitiesCurrent48.552.954.550.647.036.640.938.840.843.436.342.235.435.234.754.161.059.258.050.945.549.251.950.051.949.046.452.654.858.560.043.038.340.949.843.553.4
aPercentage of Liabilities6.24.85.64.64.85.39.88.67.67.26.87.26.86.86.77.16.47.16.85.87.17.25.64.94.96.55.96.95.75.04.94.25.56.77.67.87.2

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value722784787809786106511551267121612131187727968952933944719738768653870922998891879118911891158114511231113112610109749531163939
bPercentage of LiabilitiesCurrent5.56.16.47.17.811.111.411.79.88.78.25.48.08.06.810.49.211.310.47.510.310.813.611.511.714.214.314.914.713.912.322.620.322.822.827.422.2
aPercentage of Liabilities2.63.02.62.62.52.82.02.02.02.02.12.11.51.61.81.61.41.01.21.11.11.41.11.11.10.81.31.41.41.51.41.30.90.90.90.90.8

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value15151328167515921769192620671931
bPercentage of LiabilitiesCurrent11.610.313.714.017.420.020.417.9
aPercentage of Liabilities2.32.42.32.11.81.91.51.7

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value725252302238236270367302562589435462399386405262381476413236
bPercentage of LiabilitiesCurrent5.92.23.02.52.32.53.02.23.94.43.63.92.94.25.24.05.25.44.93.1
aPercentage of Liabilities0.40.70.80.60.40.60.60.50.50.50.70.60.30.40.30.30.30.40.30.8

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value802715748273328268269306404340642674566594542472491348467561497320
bPercentage of LiabilitiesCurrent6.15.56.12.43.22.82.62.83.32.44.45.04.75.03.95.26.35.36.36.45.94.1
aPercentage of Liabilities0.60.80.90.70.50.70.70.60.70.70.80.70.40.50.40.30.30.40.30.90.80.9

Accounts Payable Current

us-gaap:AccountsPayableCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3348324833273800334831133207353231323134301134413044282628742883298727272839304825022633247523142369221021982446235921832125144413881297133113731345
bPercentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities3.73.63.63.43.53.63.84.04.24.33.93.94.14.14.44.44.24.94.54.14.44.23.43.33.53.93.43.63.64.23.83.73.94.43.83.73.8

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value245279291295277249253265218205186205239222206209201194222215207205254270184138186195190161167210
bPercentage of AccountsPayableCurrent7.38.68.77.88.38.07.97.57.06.56.26.07.97.97.27.26.77.17.87.18.37.810.311.77.86.28.58.08.17.47.914.5
aPercentage of Liabilities0.50.30.30.30.30.30.20.30.50.40.30.30.30.40.30.30.30.20.30.30.20.20.20.20.30.30.30.30.30.30.30.3

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value520478491607576547491568579547518645625609645660693580534598571505502449474432384379326349277325305303277332274
bPercentage of AccountsPayableCurrent15.514.714.816.017.217.615.316.118.517.517.218.720.521.522.422.923.221.318.819.622.819.220.319.420.019.517.515.513.816.013.022.522.023.420.824.220.4
aPercentage of Liabilities0.80.90.70.80.80.80.50.60.60.70.70.80.80.80.90.80.91.00.90.91.01.00.80.70.70.70.60.60.70.70.60.60.70.70.60.50.6

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1583151715661847145012641447177314921527148216101465127112901583167615281634175913181508119111521254113411621346150113101229753746670761749826
bPercentage of AccountsPayableCurrent47.346.747.148.643.340.645.150.247.648.749.246.848.145.044.954.956.156.057.657.752.757.348.149.852.951.352.955.063.660.057.852.153.751.757.254.661.4
aPercentage of Liabilities2.31.92.01.81.91.92.22.42.72.42.02.02.22.02.12.52.22.82.62.32.52.31.51.51.71.81.71.71.72.11.71.51.72.11.81.71.8

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value382375379370387349379370285278288342282269261281298319334337303298389285249264224244200198213262257244222201164
bPercentage of AccountsPayableCurrent11.411.511.49.711.611.211.810.59.18.99.69.99.39.59.19.710.011.711.811.112.111.315.712.310.511.910.210.08.59.110.018.118.518.816.714.612.2
aPercentage of Liabilities0.40.50.60.60.60.60.40.40.40.40.40.50.40.50.70.50.50.50.50.50.40.40.30.30.30.40.30.30.30.40.40.40.40.40.40.40.4

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value416426441496505514469348
bPercentage of AccountsPayableCurrent12.413.113.313.115.116.514.69.9
aPercentage of Liabilities0.40.60.60.60.60.50.50.5

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value177175188214234245181139168157141209139127129145
bPercentage of AccountsPayableCurrent5.35.45.75.67.07.95.63.95.45.04.76.14.64.54.55.0
aPercentage of Liabilities0.20.20.10.20.20.20.20.20.20.20.30.30.20.20.20.2

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value12096128749311410480275269201146164216266143268292264170
bPercentage of AccountsPayableCurrent3.62.53.82.42.93.23.32.69.17.86.65.25.77.58.95.29.49.610.67.3
aPercentage of Liabilities0.30.40.50.40.20.40.30.20.20.20.30.30.10.10.10.10.10.10.10.1

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value1488912096128749311410480275269201146164216266143268292264170
bPercentage of AccountsPayableCurrent4.42.73.62.53.82.42.93.23.32.69.17.86.65.25.77.58.95.29.49.610.67.3
aPercentage of Liabilities0.30.40.50.40.20.40.30.20.20.20.30.30.10.10.10.10.10.10.10.10.10.2

Taxes Payable Current

us-gaap:TaxesPayableCurrent



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value43144641237372329315036065305285315353297297264
bPercentage of TaxesPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities0.70.80.70.60.60.50.50.10.50.20.40.80.40.50.50.5

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value64214671782342162226
bPercentage of TaxesPayableCurrent14.84.711.219.010.87.813.85.16.28.8
aPercentage of Liabilities0.10.00.00.10.00.10.10.10.00.1

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-03-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value56657160330631506565591556261598362
bPercentage of TaxesPayableCurrent13.014.617.216.145.621.5100.018.1100.019.354.419.717.319.927.923.5
aPercentage of Liabilities0.20.20.10.10.10.30.10.10.10.20.10.40.10.10.10.1

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value24730422644423918624821224724138385
bPercentage of TaxesPayableCurrent57.368.254.9119.033.163.581.367.370.081.112.8145.8
aPercentage of Liabilities1.10.10.60.40.40.40.30.30.50.30.30.3

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-31
Value615458684856
bPercentage of TaxesPayableCurrent14.212.114.118.26.619.1
aPercentage of Liabilities0.10.10.10.10.10.1

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1425136712451035935973956982933977942981106810251008842101794110181123985994932858838823859889974947862560498567561880411
bPercentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities1.12.31.51.51.31.41.61.71.71.61.51.41.51.51.61.71.61.81.61.41.51.21.21.21.21.11.11.11.11.21.11.21.11.21.41.61.6

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1381269896908182103881127784787776706875697373828372848194122128117698275107959252
bPercentage of OtherLiabilitiesCurrent9.79.27.99.39.68.38.610.59.411.58.28.67.37.57.58.36.78.06.86.57.48.28.98.410.09.810.913.713.112.48.014.615.118.916.910.512.7
aPercentage of Liabilities0.10.20.30.30.20.20.10.20.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.2

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value54148142527925529528826526629428631339233933335654645353260547847343138934832137137237737836020216119820819263
bPercentage of OtherLiabilitiesCurrent38.035.234.127.027.330.330.127.028.530.130.431.936.733.133.042.353.748.152.353.948.547.646.245.341.539.043.241.838.739.941.836.132.334.937.121.815.3
aPercentage of Liabilities0.20.50.60.50.40.50.60.70.70.70.70.60.60.70.80.80.81.00.80.70.80.50.40.40.50.40.30.30.30.30.30.30.30.30.50.50.6

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value15213312712357575281
bPercentage of OtherLiabilitiesCurrent10.79.710.211.96.15.95.48.2
aPercentage of Liabilities0.10.10.10.10.10.10.20.2

Liabilities Noncurrent

Long Term Debt

Long Term Debt Current

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value15871154521532114766149491455114346135031195011442127201203012121119261195412068120461170411334109101116010435101801035810131966094379893995910114983010055101469894962393048134
bPercentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities22.324.125.826.225.624.817.718.417.717.416.617.017.618.218.017.618.517.418.117.417.817.714.114.013.913.814.313.013.616.017.017.217.417.117.417.618.0

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value173217341744164016211610161215361510149715031427136913591373132012891277127312031151110510901005958908885808793797784817
bPercentage of RetainedEarningsAccumulatedDeficit10.911.211.411.110.811.111.211.412.613.111.811.911.311.411.510.910.710.911.211.010.310.610.79.79.59.49.48.28.07.98.08.1
aPercentage of Liabilities2.01.41.41.41.41.61.61.71.81.91.91.91.92.01.91.91.91.61.61.61.61.71.71.71.81.91.91.91.92.02.02.0

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value3778374638623724421442924303431022602119253422753072289229562701
bPercentage of RetainedEarningsAccumulatedDeficit23.824.225.225.228.229.530.031.918.918.519.918.925.324.224.722.4
aPercentage of Liabilities4.03.53.43.52.62.92.42.65.15.15.14.94.34.44.34.3

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value138413321320124211241005914108710521012996941918865835780771751750681664662658649630620631593598562568559565546536522426
bPercentage of RetainedEarningsAccumulatedDeficit8.78.68.68.47.56.96.48.18.88.87.87.87.67.37.06.56.46.46.66.25.96.36.56.36.26.46.76.06.05.65.85.65.65.55.65.65.2
aPercentage of Liabilities1.21.41.41.41.41.41.01.01.11.01.11.11.11.11.21.11.11.11.21.11.11.11.01.01.11.11.11.21.21.31.11.21.31.41.51.51.6

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value1148115111351104110910981069106310469911118
bPercentage of RetainedEarningsAccumulatedDeficit7.27.47.47.57.47.57.57.98.88.29.3
aPercentage of Liabilities1.61.11.21.31.31.31.31.31.31.31.3

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-2963-2990-3012-2995-2869-2921-2965-2487-2589-2633-2670-2660-2523-2565-2596-2624-2596-2626-2673-2684-1917-1906-2036-2040-2661-2673-2673-2767-2405-2313-2199-2450-2540-2509-2397-2423-2089
bPercentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities-5.7-6.3-6.4-6.6-6.4-6.0-4.0-4.2-4.3-4.9-4.7-4.7-4.6-3.6-3.6-3.2-3.2-4.3-4.3-3.9-3.8-3.9-3.1-3.0-2.9-3.0-3.0-3.0-2.9-2.9-3.5-3.5-3.3-3.5-3.4-3.4-3.4

dei:LegalEntity

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-36-36-36-38-31-33-34-37-36-40-41-54-56-65-64-63-60-47-53-361137193214243275409513752904116791556569094310131157
bPercentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax1.21.21.21.31.11.11.11.51.41.51.52.02.22.52.52.42.31.82.01.3-0.6-1.9-9.5-10.5-9.1-10.3-15.3-18.5-31.3-39.1-53.1-37.3-22.2-27.5-39.3-41.8-55.4
aPercentage of Liabilities3.22.62.51.81.42.32.11.61.30.90.70.50.40.40.30.10.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3123305331582130216020872067209718991828185318271928187618861491223125282166214721042133209325402514263526251650169117361708126812531137109111021309
bPercentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Liabilities3.62.92.93.03.23.13.13.23.02.94.64.64.44.53.73.63.53.43.53.83.32.22.22.22.22.12.12.12.22.52.42.52.52.53.63.53.5

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value621592582630633560572562577541523529526521512507954104988188986884181899499410101026484484506403426405470394402716
bPercentage of OtherLiabilitiesNoncurrent19.919.418.429.629.326.827.726.830.429.628.229.027.327.827.134.042.841.540.741.441.339.439.139.139.538.339.129.328.629.123.633.632.341.336.136.554.7
aPercentage of Liabilities2.01.01.11.21.01.00.70.90.90.91.81.81.71.71.41.41.41.41.41.61.40.70.60.60.60.60.60.60.70.70.70.70.70.70.70.70.7

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value146614491528610635648686658632598615595691634637602727817764719718761745811789820789776791793839638636514504506437
bPercentage of OtherLiabilitiesNoncurrent46.947.548.428.629.431.033.231.433.332.733.232.635.833.833.840.432.632.335.333.534.135.735.631.931.431.130.147.046.845.749.150.350.845.246.245.933.4
aPercentage of Liabilities1.21.31.31.41.61.61.51.41.41.41.41.41.41.41.31.31.21.11.21.21.10.90.80.70.80.70.70.70.70.80.80.80.70.71.71.71.7

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value610617630369395403377389
bPercentage of OtherLiabilitiesNoncurrent19.520.219.917.318.319.318.218.6
aPercentage of Liabilities0.50.40.50.50.40.70.70.7

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value31131336031233731128830012612513213312416316172
bPercentage of OtherLiabilitiesNoncurrent10.010.311.414.615.614.913.914.36.66.87.17.36.48.78.54.8
aPercentage of Liabilities0.10.20.20.10.20.10.10.10.40.30.40.40.40.40.40.4

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:ExelonGenerationCoLLC, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value694275699911294981221061069976796512212412717940
bPercentage of OtherLiabilitiesNoncurrent2.22.03.53.34.85.34.95.46.65.85.55.34.05.32.94.85.75.98.51.6
aPercentage of Liabilities0.10.30.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.00.1

us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value8477694275699911294981221061069976796512212412717940
bPercentage of OtherLiabilitiesNoncurrent2.72.52.22.03.53.34.85.34.95.46.65.85.55.34.05.32.94.85.75.98.51.6
aPercentage of Liabilities0.10.30.20.20.20.10.10.10.10.10.10.10.10.10.10.10.10.10.00.10.10.1

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value70222352306171681241762679984659927271011169423711285803312341115043354061514148219845178611112126141
bPercentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value250118541044196928062367150218032779169712011082281030801473194217052479149081418921586165194920561479859157418281735994193619041220-207113217435081861
bPercentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues41.711.632.925.2-4.126.636.048.521.229.127.825.014.124.131.631.62.326.327.411.216.938.123.029.019.544.631.213.713.722.331.721.515.529.329.822.311.024.128.0

dei:LegalEntity

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value12516068938594881195870107-3824678952063
bPercentage of NetCashProvidedByUsedInOperatingActivities5.00.15.73.53.30.33.92.72.91.14.86.53.8-1.216.74.05.60.84.2
aPercentage of Revenues0.70.31.31.23.2-0.51.20.90.70.20.90.60.60.11.00.80.60.01.4

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value2112072451142111513131172323041682851712162738620720828111521517523512867181185162-4611725249-46123350
bPercentage of NetCashProvidedByUsedInOperatingActivities8.411.223.55.87.56.420.86.58.317.914.026.36.17.018.54.412.18.418.914.111.411.0142.46.63.312.221.510.3-2.56.725.42.5-2.410.1-169.1
aPercentage of Revenues6.92.7-0.91.25.42.0-0.72.63.02.91.02.13.22.93.11.63.23.22.81.33.63.11.93.61.94.02.61.43.21.92.21.32.62.72.4

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value47857691631516468134407332643145756621844284550546549251477420438-936834744558153459431291221544425-354435238247157
bPercentage of NetCashProvidedByUsedInOperatingActivities19.131.18.732.018.419.88.922.611.937.912.169.922.127.419.328.332.022.116.858.622.227.6-5.518.916.930.16.89.725.124.829.311.428.634.8171.038.413.748.68.4
aPercentage of Revenues3.55.64.59.7-7.09.310.35.56.27.27.02.41.07.25.36.0-0.17.36.16.62.88.47.48.23.812.26.99.61.78.43.84.91.45.85.57.21.07.55.4

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value10458465824501348120885510291296234740721133616057829937831586837421042911-1691230150764450656811471071795119110464985784691110-1121565
bPercentage of NetCashProvidedByUsedInOperatingActivities41.845.655.722.948.051.056.957.146.613.861.666.647.552.153.151.145.964.056.25.255.157.4-102.463.173.343.558.936.162.761.780.061.554.940.8-279.241.463.7-22.084.1
aPercentage of Revenues35.1-2.521.010.411.410.919.829.817.018.017.59.08.310.523.220.0-2.315.115.10.69.524.310.614.810.323.214.89.28.53.114.812.38.815.014.35.16.111.011.7

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value22024177247238235191522353046424724320113820319221715820816419714312715327219525021923717216229734316231364336219
bPercentage of NetCashProvidedByUsedInOperatingActivities8.813.07.412.58.59.91.38.48.517.95.322.88.66.59.410.511.38.810.625.68.712.486.76.57.418.422.715.912.013.717.38.415.628.1-7.720.420.966.111.8
aPercentage of Revenues4.97.66.95.10.37.55.64.13.74.03.34.03.24.42.42.12.03.32.42.91.83.32.63.01.82.92.73.10.74.02.71.80.22.92.52.80.83.12.5

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value458190229287358208279155392209194
bPercentage of NetCashProvidedByUsedInOperatingActivities18.310.221.914.612.88.818.68.614.112.316.2
aPercentage of Revenues2.22.74.51.82.92.63.83.32.42.55.1

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value20896817816910112659219100291471391072581601087233
bPercentage of NetCashProvidedByUsedInOperatingActivities8.35.27.84.06.04.38.43.37.95.92.413.64.93.517.58.26.32.92.2
aPercentage of Revenues0.41.11.52.43.41.51.51.90.31.32.50.71.31.31.80.90.91.22.3

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1756-1673-1786-2225-1763-1989-1857-2124-1830-1569-2411-2284-2342-2329-8548-2133-2143-1795-1751-1223-1189-1176-1011-1424-1421-1078-1471-1251-1341-1344-640-572-1957-895-1179-1857-379-949-709
bPercentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues-15.9-21.6-7.2-41.3-23.3-19.5-37.0-14.3-13.7-22.6-20.4-19.9-24.2-17.6-21.9-23.1-14.0-19.5-17.2-16.9-19.8-27.6-29.0-31.8-112.9-33.7-26.0-29.0-27.5-20.6-20.9-25.3-19.2-24.6-18.7-25.2-18.8-21.8-19.7

dei:LegalEntity

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-444-452-492-579-509-486-523-565-565-637-529-766-606-1939626-716-602-521-523-507-417-401-330-345-349-357-336-341-304-287-280269-803-232-241-269-233-203-234
bPercentage of NetCashProvidedByUsedInInvestingActivities25.327.027.526.028.924.428.226.630.940.621.933.525.983.3-7.333.628.129.029.941.535.134.132.624.224.633.122.827.322.721.443.8-47.041.025.920.414.561.521.433.0
aPercentage of Revenues-5.2-4.6-4.4-6.0-4.8-5.1-15.26.7-6.0-4.8-4.6-5.4-5.5-5.8-5.4-5.6-4.6-6.7-6.0-7.0-5.9-8.0-8.1-10.78.3-28.1-6.7-9.7-6.0-8.4-6.4-6.7-5.4-6.0-5.4-6.6-5.2-5.9-5.0

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-291-541-433-725-257-934-615-689-546-145-1212-573-1068-1006-1204-1049-1170-951-899-336-417-420-594-767-771-513-865-573-772-813-471-656-1033-565-823-1395-426-426-649
bPercentage of NetCashProvidedByUsedInInvestingActivities16.632.324.232.614.647.033.132.429.89.250.325.145.643.214.149.254.653.051.327.535.135.758.853.954.347.658.845.857.660.573.6114.752.863.169.875.1112.444.991.5
aPercentage of Revenues-14.5-9.7-8.1-31.0-16.3-12.3-19.5-16.4-10.1-13.7-11.8-9.1-14.2-8.4-11.9-12.4-8.2-7.0-6.0-4.6-10.2-14.6-15.8-15.7-15.9-14.6-11.9-7.3-13.8-1.9-6.2-8.2-6.3-11.6-2.7-8.2-4.6-7.0-3.3

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value255-317275-284250-44926416-282-2011184-60-218-641533-57216893505208-47669838151-56018-182-102-537-136237-649-1419562-250261-398203-915-638
bPercentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues-14.3-20.83.8-8.95.2-5.510.6-35.6-13.84.0-2.1-8.5-1.7-3.00.3-9.12.10.610.1-6.62.453.822.8-8.520.2-0.9-2.4-0.813.5-2.6-3.20.22.7-5.62.7-3.22.9-4.12.9

dei:LegalEntity

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value21167157412838-84134-12-1011-307404-32-868012-82-17264-55-38-5658-365264-5-34243-77-4103135-32-91
bPercentage of NetCashProvidedByUsedInFinancingActivities82.7-21.15.5-26.151.2-8.5-31.8837.54.350.20.1511.7-185.350.0-5.6-14.00.7-2.3-82.7-13.4-7.9-100.0-37.1-10.4-2027.8-145.14.96.3-178.7-32.50.6-7.324.012.8-34.9
aPercentage of Revenues-1.8-0.72.52.6-0.1-1.33.7-0.5-0.14.3-5.60.9-0.8-0.6-0.80.9-1.9-1.30.21.2-1.1-0.54.5-3.90.0-1.3-0.11.6-0.90.51.40.80.20.92.4

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value21-86349-2130-1407-23451235922-70755829618256-85314523-40344-21-57-25164301-153-134-226-612521-126572-150-12-4326
bPercentage of NetCashProvidedByUsedInFinancingActivities8.227.1126.90.752.00.2154.2-143.8-159.9-1.030.3-36.7324.3-871.919.3-31.83.3-2.4151.0-10.90.4-105.3227.83.8-316.713.7-160.8-56.1112.5-56.534.843.192.750.4219.237.7-5.94.7-4.1
aPercentage of Revenues0.6-1.0-0.2-3.311.3-2.79.8-15.3-4.8-2.3-2.34.82.7-0.4-0.9-0.34.8-0.70.00.73.6-1.30.82.73.98.1-7.90.34.10.05.1-0.34.2-0.01.4-0.03.7-1.10.2

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-306-284-376-161-302-461-57-284-655-224582-233-266-603368-58476-711-186-237381-75271-133-30-134-87-154-475453-601-182213-38-827677-367-262
bPercentage of NetCashProvidedByUsedInFinancingActivities-120.089.6-136.756.7-120.8102.7-21.6-1775.0232.3111.449.2388.3122.0942.224.010.128.2-20.3-89.449.854.6-1978.947.023.8-166.773.685.328.7349.3191.192.612.83.7-1.2-14.6207.8333.540.141.1
aPercentage of Revenues-5.9-8.312.8-18.4-0.80.10.4-4.6-12.87.6-7.2-2.5-1.4-2.2-0.5-2.21.0-12.55.5-3.3-2.1-10.96.4-0.94.9-8.7-3.0-3.06.6-2.9-7.5-3.4-0.6-5.7-3.2-1.8-4.0-3.7-3.4

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value209-39551249-47-53-71265-72-72-340217-71-69223-42-92-6-327239-82-80-356254-175-84-467259-86-88-331-67-74-11740-422-7-422
bPercentage of NetCashProvidedByUsedInFinancingActivities82.012.320.0-4.219.610.5-20.1-443.8-94.035.8-6.1566.7-99.5110.9-4.5-39.0-2.5-2.6-2.968.734.2-215.8-53.063.61411.196.282.487.0-190.4-36.313.623.3-11.929.6-44.8-10.1-207.90.866.1
aPercentage of Revenues-9.5-0.2-8.00.9-2.3-1.6-1.3-8.3-1.9-1.43.9-7.4-1.4-2.83.9-5.8-1.1-1.43.5-4.5-0.1-1.4-0.63.3-0.9-1.02.4-4.3-0.8-0.93.0-0.8-0.5-0.60.50.10.6-0.52.3

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-1071663370-38311-13145-8417966
bPercentage of NetCashProvidedByUsedInFinancingActivities-42.0-52.412.0-24.6-15.2-69.3-4.9906.229.8-89.15.6
aPercentage of Revenues0.82.3-1.01.7-0.13.9-0.40.80.32.2-1.2

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-9010255110-1589920-75160114-28-36167-103-45-11-41200
bPercentage of NetCashProvidedByUsedInFinancingActivities-35.3-32.220.0-38.7-6.0-19.83.4125.026.6-79.69.646.716.5-260.9-6.77.9-0.7-1.296.2
aPercentage of Revenues2.3-0.6-0.1-0.7-1.42.4-0.4-0.41.32.1-0.90.20.11.1-0.21.20.61.3-1.0

Net Income Loss

dei:LegalEntity

us-gaap:NetIncomeLoss

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value257108363-1782341781362224305-250423-42236-831013787165166446386443495424605382561425657512528
bPercentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues11.212.415.110.312.68.711.49.49.89.77.311.23.52.81.32.24.1-0.12.6-0.54.8-3.33.526.51.42.22.5-2.03.81.42.9

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1083107910751069110510881091
bPercentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues11.313.511.812.111.314.012.1

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value116117136125110114134
bPercentage of DepreciationDepletionAndAmortization10.710.812.711.710.010.512.3
aPercentage of Revenues1.41.41.21.41.41.51.3

us-gaap:OperatingSegments, exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value259257251244237231228
bPercentage of DepreciationDepletionAndAmortization23.923.823.322.821.421.220.9
aPercentage of Revenues2.42.92.52.82.63.32.9

us-gaap:OperatingSegments, exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value407409405414468466448
bPercentage of DepreciationDepletionAndAmortization37.637.937.738.742.442.841.1
aPercentage of Revenues4.65.85.04.74.35.34.6

us-gaap:OperatingSegments, exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value83838177757475
bPercentage of DepreciationDepletionAndAmortization7.77.77.57.26.86.86.9
aPercentage of Revenues0.80.90.80.90.91.10.9

us-gaap:OperatingSegments, exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value193188180185192180183
bPercentage of DepreciationDepletionAndAmortization17.817.416.717.317.416.516.8
aPercentage of Revenues1.92.22.02.11.92.42.2

us-gaap:OperatingSegments, exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value95939499999296
bPercentage of DepreciationDepletionAndAmortization8.88.68.79.39.08.58.8
aPercentage of Revenues1.01.11.11.11.01.21.1

Increase Decrease In Other Operating Capital Net

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value109383587326198-54495144664243984-56282311-93694-99-115222562278-137168100-233-6374235122-69-158302171532-162171
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
aPercentage of Revenues3.8-3.70.60.34.30.7-3.0-1.72.63.91.1-1.0-3.81.62.6-2.23.80.03.70.3-1.3-1.59.4-1.44.14.1-0.61.15.00.60.81.75.1-0.72.13.76.25.01.2

dei:LegalEntity

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-26377-6-21267-159476-2-231073-59-3244-20
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet-23.99.71.2-1.8-10.6-48.11.4-10.413.6111.91.4-2.441.137.91.063.4-4.6-44.417.4
aPercentage of Revenues-0.20.7-0.4-0.90.01.5-0.3-0.00.10.60.1-0.20.10.3-0.2-0.10.10.5-0.3

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value44714834822-618138-215241-1-27301309442-93967536-44-55182-29-34-1129-31-12715723-26
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet40.41.82.425.524.2-40.7-12.356.257.6-50.011.848.81.8-9.69.6-139.813.5-42.480.9436.429.31800.0-15.840.1108.3-29.014.61.6174.3-13.2-9.8-10.1-99.476.7-12.0
aPercentage of Revenues-0.50.53.00.2-0.3-0.52.0-0.0-0.6-0.52.8-0.9-0.60.61.11.3-1.10.61.31.90.4-0.4-0.00.50.6-0.30.41.0-0.60.30.50.90.10.10.5

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value91151211784-1017657-29-8349-1-66-24-14-7632-34917-14-7224-281259-23118203272-169-733547181-77-18
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet8.330.020.654.62.018.535.639.6-43.9-197.611.2-1.2117.9-8.5-4.581.74.634.3-7.877.3-5.5-3600.08.620.47.159.099.1-28.627.013.659.023.2-5.7-243.316.1313.3565.647.5-10.5
aPercentage of Revenues-0.4-1.83.41.00.7-1.60.2-0.41.50.50.30.3-3.81.00.2-0.50.3-1.2-0.20.20.1-0.50.4-1.1-0.2-0.3-0.7-0.00.6-1.1-0.30.71.8-0.10.02.01.31.50.1

exc:DelmarvaPowerandLightCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-41610209-15-73111623219429-81818-14
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet-3.74.21.76.14.527.8-1.421.516.714.35.22.4-33.914.92.98.62.6-18.212.2
aPercentage of Revenues-0.20.30.2-0.10.10.60.20.00.30.10.10.4-0.1-0.20.10.20.10.2-0.0

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value391641874-5870142-35231316727-1369148-218628-118-85-118311-47103-27-59159-67219480-8-438820-718331
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet35.842.831.91.2-29.3-129.628.7-24.334.831.038.032.123.224.547.6234.490.5119.273.9-536.4121.5-2350.037.119.7-3.09.0-68.2106.328.440.065.611.627.2293.39.2-46.756.2-1.918.1
aPercentage of Revenues0.70.10.3-0.20.41.9-0.8-0.21.71.60.3-1.12.60.1-0.1-0.41.4-0.84.5-1.6-1.0-1.88.5-3.32.01.0-0.10.31.90.20.3-0.41.50.9-0.60.02.02.10.4

exc:PecoEnergyCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-6-2119-3-76-91141-24-41-1585-41-47195-14-42-1272-58-39-13127-41-21138-73-30-23110-42-80-54162-42-110-79153
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet-5.5-0.520.3-0.9-38.4168.528.5-16.7-62.1-35.719.4-48.883.90.430.515.1-6.112.1-62.6-263.6-15.2-650.045.729.9-1.211.0-16.3115.9-40.5-9.890.260.950.6-180.074.7-280.0-343.848.889.5
aPercentage of Revenues3.4-1.8-2.1-0.93.2-1.2-1.5-1.12.3-0.4-0.5-1.20.60.2-0.0-0.71.8-0.2-0.6-0.80.8-0.2-0.6-0.21.30.0-0.5-0.51.0-0.2-0.5-0.31.5-1.1-0.8-0.01.3-0.0-0.1

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-125361-322338724-464577475
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet-11.013.810.4-98.816.7-161.14.8-322.286.4176.217.1
aPercentage of Revenues0.91.00.7-5.50.21.10.4-3.70.60.7-0.1

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value15337274670214344183745363895581818
bPercentage of IncreaseDecreaseInOtherOperatingCapitalNet13.80.86.38.323.2-129.64.229.966.742.98.453.6-64.313.52.9-5.48.4-18.2-15.7
aPercentage of Revenues0.20.30.80.10.10.50.40.60.40.20.50.50.20.90.50.30.40.00.2

Cash And Cash Equivalents Period Increase Decrease

us-gaap:CashAndCashEquivalentsPeriodIncreaseDecrease



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1000-136-467-5401293-71-91-305667-73-26-1262250687-5542-76312514189-53-8851401448-695-35653219-714-214351628-295-5550975-1125-11231567-1356514
bPercentage of CashAndCashEquivalentsPeriodIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Proceeds From Repayments Of Short Term Debt

exc:AmortizationOfDebtFairValueAdjustment



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-4-3-5-4-3-5-4-4-5-2-3-3-3173-28-922-19-14-1262-6-13-983-23
bPercentage of AmortizationOfDebtFairValueAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:AmortizationOfRegulatoryAssetDebtCosts



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value322222322233170-3333233324543655566666
bPercentage of AmortizationOfRegulatoryAssetDebtCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:AmortizationRateStabilizationDeferral



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value2-4-614-1367-316-141428142013201525151713201720-1301824123
bPercentage of AmortizationRateStabilizationDeferral100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:CashRemittedToVIE

exc:AtlanticCityElectricCompany, exc:ATF



Period End2019-03-312018-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value481320121416181413
bPercentage of CashRemittedToVIE100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:ChangeReceivablesPayablesFromAffiliates

exc:AtlanticCityElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-4410-451-1-54128-20012-2
bPercentage of ChangeReceivablesPayablesFromAffiliates100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

exc:ChangesInOptionPremiumsCollectedReceived



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value35-42-6709277-4326421427-17-31-5-17-5-170-6-15-22873-814810062-21-19-19238681-66
bPercentage of ChangesInOptionPremiumsCollectedReceived100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:EffectiveIncomeTaxRateReconciliationChangeinEnactedTaxLawPercent



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-0.065-0.078-0.047-0.068-0.052-0.06
bPercentage of EffectiveIncomeTaxRateReconciliationChangeinEnactedTaxLawPercent100.0100.0100.0100.0100.0100.0

exc:EffectiveIncomeTaxRateReconciliationQualifiedDecommissioningInvestmentIncomePercent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value0.0320.0510.072-0.0279999999999999970.0240.002-0.004-0.00200000000000000180.0260.643
bPercentage of EffectiveIncomeTaxRateReconciliationQualifiedDecommissioningInvestmentIncomePercent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:EnergyRelatedOptions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-226376110-7-8415-49-3-8-93-918930293231172244214155362835343434-19-18-18-18
bPercentage of EnergyRelatedOptions100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:EstimatedPercentOfGasPurchasesBeingHedged

exc:PecoEnergyCo



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.20.00.00.00.20.00.0-0.049999999999999990.25-0.049999999999999990.00.30.00.00.30.00.00.30.00.00.00.3
bPercentage of EstimatedPercentOfGasPurchasesBeingHedged100.00.00.00.0100.00.00.0100.0100.0100.00.0100.00.00.0100.00.00.0100.00.00.00.0100.0

dei:LegalEntity, us-gaap:Range

exc:ExpectedGenerationHedgedInNextTwelveMonths

exc:ExelonGenerationCoLLC, us-gaap:Maximum



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.93-0.089999999999999970.0100000000000000090.060000000000000050.94-0.130.020000000000000018-0.0100000000000000091.00.0100000000000000090.0100000000000000090.99-0.0100000000000000090.0400000000000000360.970.060000000000000050.0100000000000000090.94-0.0500000000000000440.010000000000000009-0.0200000000000000181.01
bPercentage of ExpectedGenerationHedgedInNextTwelveMonths100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:Range

exc:ExpectedGenerationHedgedInYearThree

exc:ExelonGenerationCoLLC, us-gaap:Maximum



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.41-0.160000000000000030.070.080000000000000020.36-0.190.060.089999999999999970.330.069999999999999950.099999999999999980.40.0500000000000000440.089999999999999970.40.089999999999999970.089999999999999970.4-0.180.070.080000000000000020.36
bPercentage of ExpectedGenerationHedgedInYearThree100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:Range

exc:ExpectedGenerationHedgedInYearTwo

exc:ExelonGenerationCoLLC, us-gaap:Maximum



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.67-0.260.109999999999999990.079999999999999960.66-0.240.079999999999999960.109999999999999990.630.069999999999999950.090000000000000080.720.0399999999999999250.100000000000000090.70.109999999999999990.109999999999999990.67-0.219999999999999970.059999999999999940.080000000000000070.73
bPercentage of ExpectedGenerationHedgedInYearTwo100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

exc:FairValueInputsForwardHeatRate

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3, us-gaap:Maximum, us-gaap:IncomeApproachValuationTechnique



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value11.00.00.01.010.00.09.90.0100000000000000090.090.00.0
bPercentage of FairValueInputsForwardHeatRate100.00.00.0100.0100.00.0100.0100.0100.00.00.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

exc:FairValueInputsRenewableFactor

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3, us-gaap:Maximum, us-gaap:IncomeApproachValuationTechnique



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value1.2-0.0100000000000000090.010000000000000009-0.0200000000000000181.22-0.0500000000000000440.0400000000000000360.01.210.0
bPercentage of FairValueInputsRenewableFactor100.0100.0100.0100.0100.0100.0100.00.0100.00.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossChangeInCollateral

exc:ExelonGenerationCoLLC, us-gaap:Derivative, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value-81194449-10561-11-31-38-9031-32-50-4390-3012-59-79-34
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityGainLossChangeInCollateral100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInNoncurrentPayablesToAffiliates

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioningTrustFundInvestments, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-312014-09-302014-06-30
Value11-1-4-37-7049-2684357038
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInNoncurrentPayablesToAffiliates100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

exc:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInRegulatoryassets

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-31
Value910-715-1121-2126-24-14-2344-18-2018-34
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisIncludedInRegulatoryassets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:GainLossInvestmentIncomeNuclearDecommissioningTrustFunds



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value119166419-36515926-47298208180253419011393133-255-3492108-1821258137124-3712145130-28178136-1984579116192-13478
bPercentage of GainLossInvestmentIncomeNuclearDecommissioningTrustFunds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:ImpactsEnergyInfrastructureModernizationAct



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value5652-2855-13-184-9102724-441535-14-43-24-12346-8541-13465807749-5326-31-38
bPercentage of ImpactsEnergyInfrastructureModernizationAct100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

exc:IntersegmentRevenueNetOfPurchasePowerAndFuel

us-gaap:IntersegmentElimination, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value40183373856885621297944621237034
bPercentage of IntersegmentRevenueNetOfPurchasePowerAndFuel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

exc:NuclearFuelAmortization

us-gaap:OperatingSegments, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-30
Value35-5-11018201546298-28
bPercentage of NuclearFuelAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

exc:OtherComprehensiveIncomeUnrealizedGainLossOnEquityInvestmentsArisingDuringPeriodTax

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss



Period End2019-06-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1100-1-110-40012
bPercentage of OtherComprehensiveIncomeUnrealizedGainLossOnEquityInvestmentsArisingDuringPeriodTax100.0100.00.00.0100.0100.0100.00.0100.00.00.0100.0100.0

exc:OtherComprehensiveIncomeUnrealizedIncomeLossOnEquityInvestmentsArisingDuringPeriodNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-312011-09-30
Value5-2-2-1021-11036-4-4-3-30000-30125516828-2217600
bPercentage of OtherComprehensiveIncomeUnrealizedIncomeLossOnEquityInvestmentsArisingDuringPeriodNetOfTax100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

exc:OtherDecommissioningRelatedActivity



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-140-58-2023722-30-31-100-69-60-84-147-114-68-55-5119-6-44-30-17-50-35279-482-64253-469-7146-973324577-6635
bPercentage of OtherDecommissioningRelatedActivity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:OtherNoncashIncomeExpenseNet



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1-38469-76735420-2-62329-14-84159-15-11-22-19-181-2021-1-11-424-82130-1-7
bPercentage of OtherNoncashIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

exc:RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsNonregulatoryAccounting



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3323054455814356445974323135392134187429573938251235161425101948613161013121411
bPercentage of RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsNonregulatoryAccounting100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsRegulatoryAccounting



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value67775430214216464915921168565790342939937149556843351384736463350608016384336414949
bPercentage of RealizedGainLossInvestmentIncomeNuclearDecommissioningTrustFundsRegulatoryAccounting100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:RegulatoryOffsetNuclearDecommissioningTrustFundActivity



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value125141348-28111023-24166161160234-816811795108-207-2810688-2920494208189-4019077208-31277190-28170151188292-215128
bPercentage of RegulatoryOffsetNuclearDecommissioningTrustFundActivity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

exc:RevenueNetOfPurchasePowerAndFuelFromExternalCustomers

us-gaap:OperatingSegments, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value10052109-50112190-131137112-110161231131-164356
bPercentage of RevenueNetOfPurchasePowerAndFuelFromExternalCustomers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

exc:RevenueNetofPurchasePowerAndFuel

exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1407014223197258-46199241-31205293254-94390
bPercentage of RevenueNetofPurchasePowerAndFuel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:UnrealizedGainLossNuclearDecommissioningTrustFundsNonregulatoryAccounting



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value55-98280-34072-120-9617411170166-22116485277-218-964034-41128137646-4064471-356584-141114356107-9435
bPercentage of UnrealizedGainLossNuclearDecommissioningTrustFundsNonregulatoryAccounting100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:UnrealizedGainLossNuclearDecommissioningTrustFundsRegulatoryAccounting



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8998379-380-66-194-7520244-13222-701555279103-301-1334854-10717261210103-10219534202-97247149-36328111199324-318111
bPercentage of UnrealizedGainLossNuclearDecommissioningTrustFundsRegulatoryAccounting100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:UnrecognizedTaxBenefitsInterestIncome



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value10122041108411000-125-21000-1251014007433000
bPercentage of UnrecognizedTaxBenefitsInterestIncome100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.00.00.00.0100.0100.0100.0100.00.00.0100.0100.0100.00.0100.00.00.0100.0100.0100.00.00.00.0

us-gaap:AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value127320325239240118188297118109168252804253277235344356131295272-1614162345231-2618276429530-1473325
bPercentage of AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AdjustmentsToAdditionalPaidInCapitalOther

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6361631131621121138438384100
bPercentage of AdjustmentsToAdditionalPaidInCapitalOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfFinancingCosts



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value910899784099126810181718
bPercentage of AmortizationOfFinancingCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfIntangibleAssets



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-12-312012-09-302012-06-302012-03-31
Value151415-152151513491514144910141437151212-410113
bPercentage of AmortizationOfIntangibleAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfNuclearFuelLease



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value258252261263283282287280287265264297305274283
bPercentage of AmortizationOfNuclearFuelLease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfPowerContractsEmissionCredits



Period End2019-09-302018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value9-273-118207-14
bPercentage of AmortizationOfPowerContractsEmissionCredits100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:AmortizationOfRegulatoryAsset



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value124123143143134126152123117110128114127101653930435841334572594151614033312511131314165290240235
bPercentage of AmortizationOfRegulatoryAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligationAccretionExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1211261241221251221201181191191121131131111091079896979492916868716868665959565556525148495049
bPercentage of AssetRetirementObligationAccretionExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AssetRetirementObligationPeriodIncreaseDecrease

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312016-12-312016-09-302014-12-31
Value28010832486114145180165165300
bPercentage of AssetRetirementObligationPeriodIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligationRevisionOfEstimate



Period End2019-09-302019-03-312018-12-312016-12-312016-09-302016-06-302016-03-31
Value-300330402000
bPercentage of AssetRetirementObligationRevisionOfEstimate100.0100.0100.0100.00.00.00.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312012-03-31
Value96-229-244-108106177-143-4403-298-210702-74-29037293-81
bPercentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockDividendsPerShareDeclared



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.360.360.360.350.350.35
bPercentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

us-gaap:CompetitiveEnergyRevenue

us-gaap:IntersegmentElimination



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-315-287-306-270-391-217-295-266-328-312-499-354-266-180-204-151-209
bPercentage of CompetitiveEnergyRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress



Period End2019-09-302019-06-302019-03-312018-12-312018-09-30
Value-1452726166
bPercentage of ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerAssetReclassifiedToReceivable



Period End2019-09-302019-06-302019-03-312018-12-312018-09-30
Value-65-18-26-26-52
bPercentage of ContractWithCustomerAssetReclassifiedToReceivable100.0100.0100.0100.0100.0

us-gaap:CostOfGoodsAndServicesEnergyCommoditiesAndServices



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-302014-03-312013-06-302013-03-312012-03-312011-03-31
Value32043137297722773289240023162158279522182584157624402218251518483426234640062132298117652001
bPercentage of CostOfGoodsAndServicesEnergyCommoditiesAndServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CostOfPurchasedPower



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-312012-09-302012-06-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value134911591355103814381108122692811049601170878814-71333291244944703529259123464006132527432419275930262606682171114071485115214811134658
bPercentage of CostOfPurchasedPower100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CostsAndExpenses



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value755968818262810782527138864873347300739276917072773662947099600162035387746570165513545670555277528551155565555859725183430529284114355338503554392533803059
bPercentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxesAndTaxCredits



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value12897187-2039912-14-800332-8218941362134127511308212943326181-48283304142-61035236126101449418250340741613-369-4
bPercentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-11-10-11116-18-16-16107-15
bPercentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-45-44-45-46-47-47-46-48-47-47-47-47-48-47
bPercentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanContributionsByEmployer



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312016-03-232015-12-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-30
Value363331445032-84343330-9451302612251382234192918
bPercentage of DefinedBenefitPlanContributionsByEmployer100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value383838-303434343-283394141-2834242
bPercentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value4747474443444346454645474748
bPercentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value2-5-5141211-10272728-26
bPercentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1

us-gaap:PensionPlansDefinedBenefit



Period End2019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-30
Value-7040-16-1-2200
bPercentage of DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1100.00.0100.00.0100.0100.0100.0100.0100.00.00.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value2324242828282827262826272728
bPercentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Depreciation



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value9449429179119569479268778717917549871058826606579561547540531534534481473478471471449457452354337319316313299288279279
bPercentage of Depreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAmortizationAndAccretionNet



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value14711462146014601511149915011428140813171274156716131333106310579731009948101293110179089358729551017117010141119776602588562552688800737718
bPercentage of DepreciationAmortizationAndAccretionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:DistributionMadeToLimitedLiabilityCompanyLLCMemberCashDistributionsDeclared

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-302016-06-302016-03-31
Value225224225313312189188165164-1089565655
bPercentage of DistributionMadeToLimitedLiabilityCompanyLLCMemberCashDistributionsDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3533533523353353343343183153053052952952952872882862682692692672672682682672674524444512425697349349349
bPercentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateContinuingOperations



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.1560.2240.242-0.0620000000000000060.1450.1080.084-0.2680.341-72.00.178-0.0080000000000000070.390.2460.5940.0310000000000000280.1640.340.33-0.00400000000000000360.2820.332-1.3850.00400000000000000360.3740.3250.982-0.012000000000000010.3520.3040.4410.0150000000000000130.2980.3490.40.00500000000000000440.3950.2830.429
bPercentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.210.210.210.00.210.210.210.00.350.350.350.00.350.350.350.00.350.3499999969339370.350.00.350.350.350.00.350.350.350.00.350.350.350.00.350.350.350.00.350.350.35
bPercentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationDeductionsOther



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.0170.0170.0140.0080000000000000040.0250.030.0270.049-0.0020.5630.006-0.0069999999999999990.0060.057-0.051-0.0029999999999999990.038-0.013-0.018-0.002999999999999999-0.0190.0080.365-0.0029999999999999990.0220.0140.217-0.0040.025-0.0220.0050.0190.011-0.009-0.009
bPercentage of EffectiveIncomeTaxRateReconciliationDeductionsOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value0.022-0.0010.006-0.00099999999999999920.0110.015-0.007-0.0010.0050.847-0.001-0.0030.0020.0090.0050.003-0.017-0.004-0.007-0.003999999999999998-0.012-0.02-0.02
bPercentage of EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.0070.0190.0010.0060.032-0.0020.0280.0010.001-19.6060.0-0.024-0.008-0.033-0.02-0.0090.0120.0140.0040.015-0.003-0.012-0.477-0.0030.005-0.0030.0740.002-0.012-0.0230.0030.0040.001-0.011-0.007-0.0030.005-0.004-0.002
bPercentage of EffectiveIncomeTaxRateReconciliationOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.0640.0540.039-0.011000000000000001-0.0120.0340.0410.0160.022-27.4570.0090.0080.0380.023-0.0110.0059999999999999980.0270.0390.0260.0080.0110.021-0.576-0.0059999999999999980.030.0410.680.0110000000000000030.0560.0350.274-0.084999999999999990.0480.020.0550.00199999999999999830.0160.0330.038
bPercentage of EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.0410.0070.0050.0030000000000000010.0060.0090.013-0.0180.0115.2870.004-0.00099999999999999920.009-0.018-0.016-0.0030000000000000010.023-0.006-0.0090.0-0.01-0.004-0.180.004-0.015-0.018-0.2580.012-0.048-0.0070.0080.006-0.003-0.002-0.002-0.001-0.002-0.003-0.002
bPercentage of EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsOther



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312015-09-302015-06-30
Value0.0120.0090.0080.0040.0120.017-0.0280.0-0.022-10.357-0.066-0.00500000000000000440.029-0.058-0.0029999999999999990.038-0.013
bPercentage of EffectiveIncomeTaxRateReconciliationTaxCreditsOther100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:ElectricUtilityRevenue

exc:AtlanticCityElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value271254406265311271370269274275420269290290385284333
bPercentage of ElectricUtilityRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ElectricalGenerationRevenue



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312013-12-31
Value4979478149714305511344364456390845604081453532344473411745644080563214144
bPercentage of ElectricalGenerationRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1536580-155-120-72-96-46-10298190164225-1457229-389-212
bPercentage of FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioningTrustFundInvestments, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value20-1-40-1002-23310-121
bPercentage of FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss100.00.0100.0100.00.0100.00.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

us-gaap:FairValueAssumptionsExpectedVolatilityRate

exc:ExelonGenerationCoLLC, us-gaap:Derivative, us-gaap:FairValueInputsLevel3, us-gaap:Maximum, exc:OptionModelValuationTechnique



Period End2019-03-312018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.34362.08089999999999972.26910.25-1.391.40999999999999971.120.5800000000000001-2.38
bPercentage of FairValueAssumptionsExpectedVolatilityRate100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

us-gaap:FairValueInputsDiscountForLackOfMarketability

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3, us-gaap:Minimum, us-gaap:IncomeApproachValuationTechnique



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value0.040.00.00.00.040.0100000000000000020.00.00.030.0
bPercentage of FairValueInputsDiscountForLackOfMarketability100.00.00.00.0100.0100.00.00.0100.00.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioningTrustFundInvestments, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-31
Value-2-110010-1-3-9-4420-22
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1100.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioningTrustFundInvestments, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value1215172101919172048534404099286983109
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

us-gaap:FairValueInputsLevel3



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value2210120131013247-2-232233122143326716292026208-111012
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioningTrustFundInvestments, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1725293848253124232528652631173729
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

us-gaap:FairValueInputsLevel3



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value130-13-15-830-8-1000206911
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.00.00.00.0100.00.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

exc:ExelonGenerationCoLLC, us-gaap:Derivative, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value-1713616067-104-11172407211330182
bPercentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPeriodIncreaseDecrease

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value-14411-17-2425-30-25
bPercentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPeriodIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6396308-324101-12-68187145109175-14129595590-223-454769-27142267568-39661572-3310376-141114056108-9536
bPercentage of GainLossOnInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSaleOfOtherAssets



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-173331-5456-1-114-891319
bPercentage of GainLossOnSaleOfOtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSalesOfAssetsAndAssetImpairmentCharges



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-183301-5456-2014-891319827181339135-4
bPercentage of GainLossOnSalesOfAssetsAndAssetImpairmentCharges100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:GasDomesticRegulatedRevenue

exc:BaltimoreGasAndElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value308211791183302157810228119772942461636686315
bPercentage of GasDomesticRegulatedRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairmentOfLongLivedAssetsHeldForUse



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value1652718410854343510323512011911124052516200171000-6278000000
bPercentage of ImpairmentOfLongLivedAssetsHeldForUse100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.00.0100.00.00.00.0100.0100.00.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value11026441282-319476137021225132611206392871415310
bPercentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-6-6-10-5-7-6-7-9-10-9-5-133-4-10010-19337-21-9-2210-57-22-10000000
bPercentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.0

us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-30
Value-170-6-6-6-10-5-7-7-7-9-1016-5-7-3-4-1-200
bPercentage of IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:IncreaseDecreaseCashCollateralFromCounterparties



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value57-210-101-140141295-214-5873-63-11017447504206232
bPercentage of IncreaseDecreaseCashCollateralFromCounterparties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value253-160-764467426109-451203218-188-623475659208-57126521-61-60753136-515157153340-41-542205226113-11761468640-52652518664-303
bPercentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-810141174374386132109850495742347-2035373174-21588-331720158736327920681178-40-159-42733-853-351144517
bPercentage of IncreaseDecreaseInAccruedIncomeTaxesPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:IncreaseDecreaseInDueToAffiliatesCurrent

exc:PepcoHoldingsLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value730-103-613-11-1313
bPercentage of IncreaseDecreaseInDueToAffiliatesCurrent100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInInventories



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value113109-1281384107-167-1564132-109146853-1426194132-29164166230-80-385119-101-143359-104146161-78105366-67
bPercentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInReceivables



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value173-539-7939862238-133650118-29-31313638231-117-6578-523270516-150-65460615177-20170-3174-20-394-54-353-5360-57269-40
bPercentage of IncreaseDecreaseInReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value121022203221222-123512430340133212121111
bPercentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseRelatedParty



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value666666679101010101010101010101011101022666
bPercentage of InterestExpenseRelatedParty100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRevenueExpenseNet



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value409409403416393373371
bPercentage of InterestRevenueExpenseNet100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentIncomeInterest



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value12249642222326624110071212355647111
bPercentage of InvestmentIncomeInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:FairValueByAssetClass, us-gaap:StatementEquityComponents

us-gaap:MarketableSecuritiesUnrealizedGainLoss

us-gaap:AccountingStandardsUpdate201601, exc:RabbiTrustInvestments, us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss



Period End2019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1000000.01000000.00.01000000.01000000.01000000.0
bPercentage of MarketableSecuritiesUnrealizedGainLoss100.0100.00.0100.0100.0100.0

us-gaap:MinorityInterestPeriodIncreaseDecrease



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-183-17-14-23-14-9-9-12-12
bPercentage of MinorityInterestPeriodIncreaseDecrease100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value-1210596735142-1
bPercentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value7724849071527335395851871824809952044902671733096296386931999352290495738490-4378296286200606601620668
bPercentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest

exc:ExelonGenerationCoLLC



Period End2019-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value70406-2330-1-25-1180020
bPercentage of NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.0

us-gaap:OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-312011-09-302011-06-30
Value-232-62-51042-12206-4-83-12-3-54-5-50-5-102-2000
bPercentage of OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value-16-16-16-16-17-17-17-14-14-14-13-13-12-12-12-11-11-11-11-12-11-6101000
bPercentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.00.00.0

dei:LegalEntity, us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

exc:ExelonGenerationCoLLC, exc:AccumulatedEquityInvestment



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-1-10100006-55-2-2-3000000115516526
bPercentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.00.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value3021-18-1275244721024435-12-132363128-28325011-767-11131462112094-362-92-114251
bPercentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-6038165-51-18-65-32-59178011
bPercentage of OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-37-36-36-61-62-61-61-50-49-4949-44-47-46-46-55-55-55-54-38-38-38-34-57-49-50-51-42-44
bPercentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-6744-17-16-27-16-22-24-2890-23-21-1716-24-28-124898-79-6-53811-66105-59
bPercentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve

us-gaap:OtherCostAndExpenseOperating

exc:ThreeMileIsland, us-gaap:FacilityClosing



Period End2019-09-302019-06-302019-03-312017-12-312017-09-302017-06-30
Value390-831571
bPercentage of OtherCostAndExpenseOperating100.00.0100.0100.0100.0100.0

us-gaap:OtherDepreciationAndAmortization



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value107510691105108810911014100291589611151195941685632606602610582577590564547530533543505500494382348332329327464578519514
bPercentage of OtherDepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherLaborRelatedExpenses



Period End2019-09-302019-06-302018-12-312018-09-302018-06-30
Value5761565865
bPercentage of OtherLaborRelatedExpenses100.0100.0100.0100.0100.0

us-gaap:OtherNoncashIncomeExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value737-150-127-320-325-239-240-118-188-297-118-109-168-252-804-253-277-235-344-356-131-295-272-138-162-345-231-148-276-1489530-14851081-601223-1077
bPercentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNonoperatingIncome



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8921859661087648-371-6011229199929-2-32-500-215558
bPercentage of OtherNonoperatingIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

us-gaap:OtherOperatingIncome

us-gaap:IntersegmentElimination



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-1-1-1-1-1-40-1000-2-1-10-20-1-1
bPercentage of OtherOperatingIncome100.0100.0100.0100.0100.0100.00.0100.00.00.00.0100.0100.0100.00.0100.00.0100.0100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value56-32-292-28-341-7-91843614721230752229354-47-2-23-40-95-53-475962-13-15-134-18-12
bPercentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:PaymentsOfDistributionsToAffiliates

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value22522422531331118918816516416616475556565510610690613562052052053075762632112424932916001116100885206156261
bPercentage of PaymentsOfDistributionsToAffiliates100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0

us-gaap:PaymentsOfDividendsCommonStock



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value351352352333333333333315314304303293291295287286282268269266266267266268265266450490453423350349349347348347348347347
bPercentage of PaymentsOfDividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireOtherInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1590318136662444262926761248106917053506183316452999279722972410130016901747200113122360187893219538367291061939175737263039152152512471043967931966
bPercentage of PaymentsToAcquireOtherInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value168717021873209716901927188020281711173121142185187922872202218119831676178419631613128412171508136910711447164413291320149610709878351150944798706878
bPercentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionAndOtherPostretirementBenefitContributions



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value22273282117143316119183071142519239721293226910117274726276172673314135552710120882196212198
bPercentage of PensionAndOtherPostretirementBenefitContributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionAndOtherPostretirementBenefitExpense



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value112106106148145145145161161163157161161160136161159160159123122142173204212204205214206219181135136135136146147144144
bPercentage of PensionAndOtherPostretirementBenefitExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:ProceedsFromContributionsFromParent

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6361631131621121138438384100127757439127303114105567438176000000000000200
bPercentage of ProceedsFromContributionsFromParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.0100.00.00.0

us-gaap:ProceedsFromIssuanceOfLongTermDebt



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value72644840245111763581130854163521876322813143023151800247011206251111211509502415223601494697088500060005990139800
bPercentage of ProceedsFromIssuanceOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.0100.00.0100.00.00.0

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-29-20-14-14-44-20-30-19-41-19-4-12039-106-2-6-43-16-20-75-55-28-17-40-17-45-91-10-9-15-211-471-1920
bPercentage of ProceedsFromPaymentsForOtherFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-40-70540-120-418-5267261191-992-2997211254-216-24451647-150136235-141-114-57-345638127-457429233-58-31838141-3013229050-65-22433101
bPercentage of ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleAndMaturityOfOtherInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value152332073713238325572633118999716353446176715822937273722402344123716331681193212452394182587318967716771003891169136803019146346211951008957890909
bPercentage of ProceedsFromSaleAndMaturityOfOtherInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleOfPropertyHeldForSale



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value368111079081892212445020314210596281418028
bPercentage of ProceedsFromSaleOfPropertyHeldForSale100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0

us-gaap:ProceedsFromStockPlans



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value192451384015128918311219198988881071177820121119301212117814121111
bPercentage of ProceedsFromStockPlans100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProfitLoss



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-03-312010-12-312010-09-30
Value760494966105800542636193886764981248526306123309587633738181074557934957364971378297289200606601669524845
bPercentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForDoubtfulAccounts



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value44243265613642251183448561041634-48460372435182810454460204024520451654-1048
bPercentage of ProvisionForDoubtfulAccounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value222122221613182217171721191588655455664566433344552
bPercentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:PublicUtility

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount

exc:PotomacElectricPowerCompany, us-gaap:ElectricDistribution



Period End2019-01-152018-02-052018-01-022017-12-192017-03-242017-03-312016-12-312016-06-30
Value30114166696953127
bPercentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RealEstateTaxExpense



Period End2019-09-302019-06-302018-12-312018-09-302018-06-30
Value148148141145135
bPercentage of RealEstateTaxExpense100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass

us-gaap:RealizedInvestmentGainsLosses

exc:CommonwealthEdisonCo, us-gaap:InterestRateSwap, us-gaap:Derivative



Period End2019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value-5-3-463-162
bPercentage of RealizedInvestmentGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-27-27-60-60-60-60-58-58-58-58-54-57-56-56
bPercentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-03-31
Value-20-45-45-43-44-36-34-34-40-44-42-3431-44-46-46-6010218-1241296-6
bPercentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value77151516162323-24-22-15322-22-22
bPercentage of ReclassificationFromAociCurrentPeriodTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RegulatedOperatingRevenue



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-80-1345034055445737974570394643133715419737934467367631002584283724343198
bPercentage of RegulatedOperatingRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value32333438333536867785511111
bPercentage of RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:RelatedPartyTransactionPurchasesFromRelatedParty

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value368810665779815121
bPercentage of RelatedPartyTransactionPurchasesFromRelatedParty100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve

us-gaap:RestructuringAndRelatedCostIncurredCost

exc:ThreeMileIsland, us-gaap:FacilityClosing



Period End2019-09-302019-06-302019-03-312017-12-312017-09-302017-06-30
Value11375-4114112108
bPercentage of RestructuringAndRelatedCostIncurredCost100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtility, us-gaap:RestructuringCostAndReserve

us-gaap:RestructuringReserveAcceleratedDepreciation

exc:ThreeMileIsland, us-gaap:FacilityClosing



Period End2019-09-302019-06-302019-03-312017-12-312017-09-302017-06-30
Value71717410910635
bPercentage of RestructuringReserveAcceleratedDepreciation100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-5-21-25-261016545879
bPercentage of RevenueFromContractWithCustomerIncludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

us-gaap:RevenueFromPurchasedOilAndGas

us-gaap:OperatingSegments



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value878879397489947768460430918
bPercentage of RevenueFromPurchasedOilAndGas100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:RevenueFromRelatedParties

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1111111001101112111
bPercentage of RevenueFromRelatedParties100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:ConsolidationItems

us-gaap:SalesRevenueServicesGross

exc:PepcoHoldingsLLC, us-gaap:IntersegmentElimination



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-102-104-100-105-109-10-10
bPercentage of SalesRevenueServicesGross100.0100.0100.0100.0100.0100.00.0100.00.0

us-gaap:ShareBasedCompensation



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value28111718291219263123212344-5234039-2043224621293139191917391212152898918
bPercentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0032000361
bPercentage of StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensationGross



Period End2019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value002446001685
bPercentage of StockIssuedDuringPeriodSharesShareBasedCompensationGross100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value19245138401512891831121919898888101186
bPercentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensationGross



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1014-391520-31320221
bPercentage of StockIssuedDuringPeriodValueShareBasedCompensationGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TaxesExcludingIncomeAndExciseTaxes



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value452418445441469428446418456420436408449394325292310294304267306288293270277271277282290254194183207191203193232186197
bPercentage of TaxesExcludingIncomeAndExciseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrealizedGainLossOnDerivatives



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11-76-31-22784108-259-281-183-477694-3011074-14441691-194229-21-730216201416-388227542507369-96-116-148-193158-110233
bPercentage of UnrealizedGainLossOnDerivatives100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:UnrealizedGainLossOnSecurities

us-gaap:OperatingSegments, exc:GenerationAllOtherSegments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value17-74-28-2157190-266-12852-14344325187-61563
bPercentage of UnrealizedGainLossOnSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrecognizedTaxBenefitsPeriodIncreaseDecrease



Period End2019-03-312017-03-312016-12-312016-09-302016-06-30
Value3376-496328328
bPercentage of UnrecognizedTaxBenefitsPeriodIncreaseDecrease100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseGasAndPetroleumPurchased

exc:BaltimoreGasAndElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value957821321236513228353142075
bPercentage of UtilitiesOperatingExpenseGasAndPetroleumPurchased100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2072215921892301234623072384239423002945243823712338
bPercentage of UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpensePurchasedPower

exc:AtlanticCityElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value131122188122155123169121128123206129
bPercentage of UtilitiesOperatingExpensePurchasedPower100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseTaxes



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value24120922321425321823521624521322412925521715344151132
bPercentage of UtilitiesOperatingExpenseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:EntityCommonStockSharesOutstanding



Period End2019-09-302019-06-302019-03-312019-01-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312016-01-312015-09-302015-06-302015-03-312015-01-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value972971970969967965965965960960926926923922887919919861861859859859858857856856855663854853852663663662661659
bPercentage of EntityCommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:AccruedCompensationCurrent



Period End2019-09-302019-06-302018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value880767119197811991014832683708520465401
bPercentage of AccruedCompensationCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:CashCollateralHeld

exc:ExelonGenerationCoLLC



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-31
Value645647204766354934352418141621771691482062022152364996071007542
bPercentage of CashCollateralHeld100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:CashCollateralPosted



Period End2019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312014-09-30
Value253742241191923109894
bPercentage of CashCollateralPosted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:HedgingDesignation

exc:CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentLiability

exc:ExelonGenerationCoLLC, us-gaap:DesignatedAsHedgingInstrument



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-31
Value177125661192201671381559548059912
bPercentage of CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:HedgingDesignation

exc:CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentNoncurrentLiability

exc:ExelonGenerationCoLLC, us-gaap:DesignatedAsHedgingInstrument



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-31
Value100604794169779310762222220
bPercentage of CollateralAmountOffsetAgainstFairValueOfDerivativeCurrentNoncurrentLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:RelatedPartyTransactionsByRelatedParty

exc:DueFromAffiliateCurrentElectricGasUtility

exc:ExelonGenerationCoLLC, exc:BaltimoreGasAndElectricCompanyAffiliate



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312013-12-312013-06-302013-03-31
Value272423232524222124223635273325
bPercentage of DueFromAffiliateCurrentElectricGasUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:RelatedPartyTransactionsByRelatedParty

exc:DueFromAffiliateCurrentElectricUtility

exc:ExelonGenerationCoLLC, exc:AtlanticCityElectricCompany



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value4564567671088
bPercentage of DueFromAffiliateCurrentElectricUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

exc:FairValueInputsForwardGasPriceAssets

exc:ExelonGenerationCoLLC, us-gaap:Derivative, us-gaap:FairValueInputsLevel3, us-gaap:Maximum, us-gaap:IncomeApproachValuationTechnique



Period End2019-03-312018-12-312018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value11.6312.3811.1912.812.89.439.379.879.29.5310.198.95
bPercentage of FairValueInputsForwardGasPriceAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:Range, us-gaap:ValuationTechnique

exc:FairValueInputsForwardPowerPriceAssets

exc:ExelonGenerationCoLLC, exc:ProprietaryTrading, us-gaap:FairValueInputsLevel3, us-gaap:Maximum, us-gaap:IncomeApproachValuationTechnique



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value162.0174.0158.0139.0202.094.069.073.067.079.068.084.078.0
bPercentage of FairValueInputsForwardPowerPriceAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByAssetClass

exc:FairValueNetAssetsLiabilitiesExcludedFromNuclearDecommissioningTrustFundInvestments

exc:NuclearDecommissioningTrustFundInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-31
Value17614194-1308910384-8252298-31-69-48-17-3-5
bPercentage of FairValueNetAssetsLiabilitiesExcludedFromNuclearDecommissioningTrustFundInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

exc:FinancialAssetLiabilitiesNetFairValueDisclosure1

exc:AtlanticCityElectricCompany, us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value212326252729312980130194176-148-30
bPercentage of FinancialAssetLiabilitiesNetFairValueDisclosure1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

exc:FinancialAssetsFairValueDisclosure1

exc:AtlanticCityElectricCompany, us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value21232625272931298013019417614830
bPercentage of FinancialAssetsFairValueDisclosure1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:IncrementalCollateralForLossOfInvestmentGradeCreditRating

exc:BaltimoreGasAndElectricCompany



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value31466931364966283647622931283528341117947731538541861271245154
bPercentage of IncrementalCollateralForLossOfInvestmentGradeCreditRating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, exc:CreditRiskExposure

exc:InvestmentGradeExternalCreditRating

exc:ExelonGenerationCoLLC, exc:CreditCollateral



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value110001491416041258506288103117172191139184347
bPercentage of InvestmentGradeExternalCreditRating100.00.00.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, exc:CreditRiskExposure

exc:InvestmentGradeInternalCreditRating

exc:ExelonGenerationCoLLC, exc:NetExposure



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value16218017822822325331632732435142037251552147930228432141546645139850248553659849283034
bPercentage of InvestmentGradeInternalCreditRating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:InvestmentsInNonconsolidatedVariableInterestEntities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value2012032142232322382462512592682762481938075111916996263648697979897989894
bPercentage of InvestmentsInNonconsolidatedVariableInterestEntities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:LettersOfCreditHeld

exc:ExelonGenerationCoLLC



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-31
Value212644486046332921322822469678241214343230484510915289
bPercentage of LettersOfCreditHeld100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:LettersOfCreditPosted



Period End2019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312014-09-302012-12-31
Value9193421231210102235874563
bPercentage of LettersOfCreditPosted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:MgpSiteContingencyApprovedCleanupCount

exc:BaltimoreGasAndElectricCompany



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302012-03-31
Value13.013.09.013.013.013.011.013.013.013.013.02.0
bPercentage of MgpSiteContingencyApprovedCleanupCount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:MgpSiteContingencyCount

exc:BaltimoreGasAndElectricCompany



Period End2019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value000000000000001300013000
bPercentage of MgpSiteContingencyCount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:MgpSiteContingencyMonitoringCount

exc:BaltimoreGasAndElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value000000131300000000003000300
bPercentage of MgpSiteContingencyMonitoringCount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

exc:NetAssetLiabilityPositionAfterContractualRightOfOffset

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value302295490618455449579349278341282333311255-25113231-283-28216-303-277-276-210-4238655462925116
bPercentage of NetAssetLiabilityPositionAfterContractualRightOfOffset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, exc:CreditRiskExposure

exc:NonInvestmentGradeExternalCreditRating

exc:ExelonGenerationCoLLC, exc:CreditCollateral



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value394520304612413162224322519792299312924
bPercentage of NonInvestmentGradeExternalCreditRating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, exc:CreditRiskExposure

exc:NoninvestmentGradeInternalCreditRating

exc:ExelonGenerationCoLLC, exc:CreditCollateral



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value761713171118141483747434921113
bPercentage of NoninvestmentGradeInternalCreditRating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:NumberOfVariableInterestEntitiesConsolidated



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-312014-09-302014-06-302014-03-312013-12-312013-12-31
Value5.05.05.05.05.05.05.06.07.09.09.09.09.09.07.07.07.06.06.00.08.04.00.0
bPercentage of NumberOfVariableInterestEntitiesConsolidated100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

exc:NumberOfVariableInterestEntitiesNotConsolidated



Period End2019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value8.07.07.07.07.07.07.07.08.09.09.09.08.08.08.07.06.08.05.05.08.07.09.0
bPercentage of NumberOfVariableInterestEntitiesNotConsolidated100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

exc:OtherNonconsolidatedVariableInterestEntityOwnershipInterests



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value596585587598612618618627609610455439431284269289282256302243259254234255262319310212212206
bPercentage of OtherNonconsolidatedVariableInterestEntityOwnershipInterests100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, exc:CreditRiskExposure

exc:TotalCreditRiskExposure

exc:ExelonGenerationCoLLC, exc:CreditCollateral



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value57523843642731293325324495828598118148184207176219384
bPercentage of TotalCreditRiskExposure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

exc:TotalDeferredCreditsAndOtherLiabilities

exc:AtlanticCityElectricCompany, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value3540455054586774818999106114124
bPercentage of TotalDeferredCreditsAndOtherLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsPayableRelatedPartiesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-31
Value55555555888
bPercentage of AccountsPayableRelatedPartiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AccountsPayableRelatedPartiesNoncurrent

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value29602928287026062959291629703065
bPercentage of AccountsPayableRelatedPartiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AccountsReceivableRelatedPartiesCurrent

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-12-31
Value1000000.00.01000000.01000000.00.01000000.00.0
bPercentage of AccountsReceivableRelatedPartiesCurrent100.00.0100.0100.00.0100.00.0

dei:LegalEntity

us-gaap:AccountsReceivableRelatedPartiesNoncurrent

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value24872458241222172469243024642528
bPercentage of AccountsReceivableRelatedPartiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccrualForEnvironmentalLossContingenciesGross



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value507482486496486453462466429412429
bPercentage of AccrualForEnvironmentalLossContingenciesGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AccruedLiabilitiesAndOtherLiabilities

exc:PotomacElectricPowerCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value30303030303030280
bPercentage of AccruedLiabilitiesAndOtherLiabilities100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:AccruedLiabilitiesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1877170617252112196416651569183530802878300734603236275722602376157613661230153914621382136416331540138214301800150214521492125510538788521040923
bPercentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:AdditionalPaidInCapital

exc:CommonwealthEdisonCo



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value7509744673857322720970476935682267386357625061506022579557175677554855165484546853625304523051905189518851865014501650165012500349924992499249924990
bPercentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value248257340319354339369322339322346334330314351284329323365311291-293-306272-302306320293310303317199244229246-228-225
bPercentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulOtherReceivablesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312017-12-31
Value4940383431
bPercentage of AllowanceForDoubtfulOtherReceivablesCurrent100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementFrequency

us-gaap:AlternativeInvestmentsFairValueDisclosure

exc:ExelonGenerationCoLLC, exc:Middlemarketlending, us-gaap:FairValueMeasurementsRecurring



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value40636723521612713187786471230
bPercentage of AlternativeInvestmentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

dei:LegalEntity, us-gaap:PublicUtility

us-gaap:AssetRetirementObligation

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioning



Period End2019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value10329100059317992196629366947692598734900989038246
bPercentage of AssetRetirementObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:PublicUtility

us-gaap:AssetRetirementObligationCurrent

exc:ExelonGenerationCoLLC, exc:NuclearDecommissioning



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value412212996413121211104411
bPercentage of AssetRetirementObligationCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligationsNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value100891002399679679974710222101261002997339848963491119348925687558585840575507446729570037054526151945118520251495074486641264064388438083597354634943434
bPercentage of AssetRetirementObligationsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:VariableInterestEntitiesByClassificationOfEntity

us-gaap:AssetsNoncurrent

exc:AtlanticCityElectricCompany, us-gaap:VariableInterestEntityPrimaryBeneficiary



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value1919192020232223232319191818
bPercentage of AssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value1888089090491004411147
bPercentage of AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedCostsAssetRetirementCosts



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312014-12-31
Value301-10767473229-141103191476471625672
bPercentage of CapitalizedCostsAssetRetirementCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:BalanceSheetLocation

us-gaap:CashAndCashEquivalentsFairValueDisclosure

exc:AtlanticCityElectricCompany, us-gaap:CashAndCashEquivalents



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-31
Value771161025733
bPercentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value217811781314178123211028109911901545811889914889914
bPercentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:ShortTermDebtType

us-gaap:CommercialPaper

exc:BaltimoreGasAndElectricCompany, us-gaap:CommercialPaper



Period End2019-03-312018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value106357745210500012020706913540
bPercentage of CommercialPaper100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerAssetNetCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value170196187187197243283
bPercentage of ContractWithCustomerAssetNetCurrent100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerLiabilityCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value26212527372835
bPercentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:CustomerDepositsCurrent

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value26262626262628313131323335373530
bPercentage of CustomerDepositsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:DebtInstrumentFairValue

exc:AtlanticCityElectricCompany, us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value100498788789891694996998098910071058108310811044
bPercentage of DebtInstrumentFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DecommissioningFundInvestments



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value12706125131230211661124641311013149132721296612641123621106111076107371052610342101031060710712105371034910437821580717776746375597248714068416927650762266699662564086669
bPercentage of DecommissioningFundInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-07-272018-06-30
Value42542542524151590681
bPercentage of DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:DeferredCompensationLiabilityCurrentAndNoncurrent

exc:BaltimoreGasAndElectricCompany, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value55544544444434435
bPercentage of DeferredCompensationLiabilityCurrentAndNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCostsAndOtherAssets



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value31939319113165729599301723047630774306643093722611
bPercentage of DeferredCostsAndOtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCreditsAndOtherLiabilities



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value428554245642310407274104841216410064120743671428934265541619419194138034658
bPercentage of DeferredCreditsAndOtherLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredFinanceCostsNet



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value216216219213213201196185199200204200179180
bPercentage of DeferredFinanceCostsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value12133118261164211330117021148411344112221925018521185181813813776
bPercentage of DeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:DeferredTaxAssetsLiabilitiesNetNoncurrent

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value1114182125610168510165131262233
bPercentage of DeferredTaxAssetsLiabilitiesNetNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPensionPlanLiabilitiesNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3712372037343988338534123433373640554082408242483765376737713385301431343154336618091804166118763094316431613428257526102553219414751495151636583625
bPercentage of DefinedBenefitPensionPlanLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent

exc:AtlanticCityElectricCompany



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value5660636770737673767984
bPercentage of DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeAssetNotionalAmount



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-31
Value864827122314329159659498118857718869331073130311551236794
bPercentage of DerivativeAssetNotionalAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeAssets

exc:ExelonGenerationCoLLC, us-gaap:CommodityContract



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1107124611251238149113041381
bPercentage of DerivativeAssets100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeAssetsCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value60152665280469679997897669983384791775475911851365111614051117127974462975672773084566693892811701491432478438462487376
bPercentage of DerivativeAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeAssetsNoncurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value487537454452449457527337426464539492669546841758801811913773524482571607779772706937103912411389650300324425409649
bPercentage of DerivativeAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeCollateralObligationToReturnCash



Period End2019-09-302018-12-312015-09-302015-06-302015-03-31
Value9647133062
bPercentage of DerivativeCollateralObligationToReturnCash100.0100.0100.0100.0100.0

us-gaap:DerivativeCollateralObligationToReturnSecurities



Period End2019-09-302018-12-312015-09-302015-06-302015-03-31
Value5844251814
bPercentage of DerivativeCollateralObligationToReturnSecurities100.0100.0100.0100.0100.0

us-gaap:DerivativeCollateralRightToReclaimCash



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-31
Value7877543503748537775481296471385243
bPercentage of DerivativeCollateralRightToReclaimCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:DerivativeCollateralRightToReclaimSecurities

exc:ExelonGenerationCoLLC



Period End2019-09-302018-12-312015-09-302015-06-302015-03-312014-12-31
Value273367474511626672
bPercentage of DerivativeCollateralRightToReclaimSecurities100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:DerivativeFairValueAmountOffsetAgainstCollateralNet

us-gaap:FairValueInputsLevel1



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value93975257183680655971757185123350476353277425434286
bPercentage of DerivativeFairValueAmountOffsetAgainstCollateralNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral

exc:CommonwealthEdisonCo, us-gaap:Derivative, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value-240-249-259-252-267-256-277-256-282-258-244-221-247
bPercentage of DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:DerivativeFairValueOfDerivativeLiability

exc:ExelonGenerationCoLLC



Period End2019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value124911191667-1723170416992141926916942994960975912-979-9321533-1558-1420-1433-997-1102-1178-1056-1849
bPercentage of DerivativeFairValueOfDerivativeLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral

exc:ExelonGenerationCoLLC, exc:ProprietaryTrading, us-gaap:FairValueInputsLevel3



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value-645658634326-15-6-33337
bPercentage of DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeFairValueOfDerivativeNet

exc:ExelonGenerationCoLLC, us-gaap:CommodityContract



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value577548584722880923977
bPercentage of DerivativeFairValueOfDerivativeNet100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue



Period End2019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-31
Value-27-44-40-200112-101611810
bPercentage of DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue100.0100.0100.0100.00.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeLiabilities

exc:ExelonGenerationCoLLC, us-gaap:CommodityContract



Period End2019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value530698541516611-381-404
bPercentage of DerivativeLiabilities100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeLiabilitiesCurrent



Period End2019-09-302019-06-302019-03-312018-12-312018-