XEL


Line plots across dimensions of each concept
Tables

Table of contents



us-gaap:CommonStockValue

us-gaap:CommonStockSharesOutstanding
us-gaap:StatementEquityComponents

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted
us-gaap:MajorCustomers, us-gaap:ProductOrService
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:MajorCustomers, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems
us-gaap:Revenues
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CostsAndExpenses

us-gaap:OperatingIncomeLoss

us-gaap:InterestExpense

us-gaap:InterestAndDebtExpense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:IncomeTaxesPaidNet

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:NetIncomeLoss
us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:Assets

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:AccountsReceivableNetCurrent

us-gaap:InventoryNet

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross
us-gaap:PropertyPlantAndEquipmentByType

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
us-gaap:PropertyPlantAndEquipmentByType

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:OtherAssetsNoncurrent

us-gaap:LiabilitiesCurrent

us-gaap:AccountsPayableCurrent

us-gaap:TaxesPayableCurrent

us-gaap:OtherLiabilitiesCurrent

us-gaap:DividendsPayableCurrent

us-gaap:LongTermDebt

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:IncreaseDecreaseInInventories

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquireInvestments

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends

us-gaap:RepaymentsOfLongTermDebt

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:ShareBasedCompensation

us-gaap:UnrecognizedTaxBenefits

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:ProceedsFromRepaymentsOfShortTermDebt

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:AllowanceForFundsUsedDuringConstructionInvestingActivities

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
us-gaap:StatementEquityComponents
us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:DebtRelatedCommitmentFeesAndDebtIssuanceCosts

us-gaap:DeferredIncomeTaxExpenseBenefit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:DepreciationAmortizationAndAccretionNet
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeGainLossOnDerivativeNet
us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:DividendsCommonStock
us-gaap:StatementEquityComponents

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments

us-gaap:EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCredits

us-gaap:EquityMethodInvestmentDividendsOrDistributions
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsPayable

us-gaap:IncreaseDecreaseInEmployeeRelatedLiabilities

us-gaap:IncreaseDecreaseInOtherCurrentAssets

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities

us-gaap:IncrementalCommonSharesAttributableToContingentlyIssuableShares

us-gaap:InterestPaidNet
us-gaap:ShortTermDebtType
us-gaap:LineOfCreditFacilityInterestRateDuringPeriod

us-gaap:OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax
us-gaap:StatementEquityComponents
us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
us-gaap:StatementEquityComponents
us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherCostOfOperatingRevenue

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsToAcquireProductiveAssets
xel:ShareIssuanceProgram
us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromSaleAndMaturityOfOtherInvestments

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:StatementEquityComponents
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:RegulatedAndUnregulatedOperatingRevenue
us-gaap:ConsolidationItems

us-gaap:RegulatedOperatingRevenueGas
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:ProductOrService
us-gaap:RevenueNotFromContractWithCustomer
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
us-gaap:ShortTermDebtType
us-gaap:ShorttermDebtAverageOutstandingAmount
us-gaap:ShortTermDebtType
us-gaap:ShorttermDebtMaximumAmountOutstandingDuringPeriod

us-gaap:StockIssued1
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesNewIssues

us-gaap:StockIssuedDuringPeriodValueNewIssues
us-gaap:StatementEquityComponents

us-gaap:TaxesExcludingIncomeAndExciseTaxes

us-gaap:UnrealizedGainOnSecurities

us-gaap:UnrealizedLossOnSecurities

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense

us-gaap:UnregulatedOperatingRevenue
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:UtilitiesOperatingExpenseDepreciationAndAmortization

us-gaap:UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses

xel:ConservationandDemandSideManagementProgramExpenses

xel:CostofnaturalGasSoldandTransported

xel:CreditLossesTopic326ASCTopic326
us-gaap:RetirementPlanType
xel:DefinedBenefitPlanCreditsNotRecognizedDueToEffectsofRegulation
us-gaap:RetirementPlanType
xel:DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
xel:DerivativeInstrumentsGainLossReclassifiedToRegulatoryAssetsAndLiabilitiesNet

xel:EffectiveIncomeTaxRateReconciliationOtherRegulatoryItemsPercent

xel:ElectricFuelandPurchasedPower
us-gaap:DerivativeInstrumentRisk
xel:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityNetLossesGainsRecognizedAsRegulatoryAssetsAndLiabilities

xel:IncreaseDecreaseinAccruedUnbilledRevenues

xel:Inventorytransferstoplantpropertyandequipment

xel:NuclearFuelAmortization
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
xel:Pretaxgainslossesreclassifiedintoincomeduringtheperiodfromregulatoryassetsandliabilities
us-gaap:HedgingDesignation

xel:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfDebt

xel:RegulatedOperatingRevenueElectric
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
xel:RevenuesIncludingIntersegmentRevenues

us-gaap:AccountsReceivableGrossCurrent
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:AccrualForEnvironmentalLossContingenciesGross

us-gaap:AccumulatedDeferredInvestmentTaxCredit

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:AlternativeInvestment
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:AssetRetirementObligationsNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType
us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:AvailableForSaleSecurities
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:AvailableForSaleSecuritiesDebtSecurities
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:AvailableForSaleSecuritiesEquitySecurities
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:ContractWithCustomerLiabilityNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility
us-gaap:DebtLongtermAndShorttermCombinedAmount
us-gaap:CreditFacility
us-gaap:CreditFacility, dei:LegalEntity
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType
us-gaap:DecommissioningTrustAssetsAmount
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DerivativeAssetCollateralObligationToReturnCashOffset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation
us-gaap:DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset
us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation
us-gaap:DerivativeAssets
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:DerivativeInstrumentsAndHedges

us-gaap:DerivativeInstrumentsAndHedgesLiabilities

us-gaap:DerivativeInstrumentsAndHedgesLiabilitiesNoncurrent

us-gaap:DerivativeInstrumentsAndHedgesNoncurrent
us-gaap:BalanceSheetLocation
us-gaap:DerivativeLiabilities
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:DerivativeLiabilityCollateralRightToReclaimCashOffset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation
us-gaap:DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset
us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeNonmonetaryNotionalAmount

us-gaap:EquityMethodInvestments
us-gaap:StatementBusinessSegments
us-gaap:DerivativeInstrumentRisk
us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs

us-gaap:GuaranteeObligationsMaximumExposure

us-gaap:InterestPayableCurrent

us-gaap:InvestmentsAndOtherNoncurrentAssets

us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:CreditFacility
us-gaap:CreditFacility, dei:LegalEntity
us-gaap:ShortTermDebtType
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:CreditFacility
us-gaap:CreditFacility, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, dei:LegalEntity

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:LongTermDebtFairValue

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OtherLongTermInvestments

us-gaap:PrepaidTaxes
us-gaap:PublicUtilitiesInventory
us-gaap:PublicUtilitiesInventory

us-gaap:RegulatoryAssetsCurrent

us-gaap:RegulatoryAssetsNoncurrent

us-gaap:RegulatoryLiabilityCurrent

us-gaap:RegulatoryLiabilityNoncurrent

us-gaap:ShortTermBorrowings
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, dei:LegalEntity
us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtWeightedAverageInterestRate

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType
us-gaap:TradingSecurities
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate

xel:AccruedUnbilledRevenues
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
xel:Basispoints
us-gaap:Range, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, dei:LegalEntity

xel:DerivativeGrossLiabilityPositionAggregateFairValue
us-gaap:Range, xel:ShareIssuanceProgram
xel:Expectedsettlementprice
us-gaap:VariableInterestEntitiesByClassificationOfEntity
xel:GeneratingCapacityUnderLongTermPurchasedPowerAgreements

xel:NetDeferredTaxLiabilityassociatedwiththeUnrecognizedTaxBenefitAmountsandRelatedNOLsandTaxCreditCarryforwards
us-gaap:AccountsNotesLoansAndFinancingReceivablesByIndustryOfCounterpartyType, us-gaap:ConcentrationRiskByType
xel:Numberofmostsignificantcounterpartiesforwholesaletradingandnontradingcommodityactivitieswithcreditexposure
us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator

xel:OtherAssetsExcludingPropertyPlantAndEquipment
us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator
xel:PercentageOfWholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties

xel:TaxBenefitsAssociatedWithNolAndTaxCreditCarryforwards

xel:UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate
us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator
xel:WholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties

Tables

  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:CommonStockValue ███▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▄▃▃▂▂▂▂▂▁▁▁▁13131311131112871287128512831272127212691269126912691268126912691269126812681267126612641263126212521244124412431236121912191218121712161212121112101205NANANA1143NANANA
us-gaap:CommonStockSharesOutstanding ██▆▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▄▄▃▃▃▂▁▁▁▁▁525524514514514514513508508507507507507507507507507507507506506505505505501497497497494487487487486486NANANA482NANANA457NANANA
 us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock███▇▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▅▅▅▅▅▄▄▄▄▄▄▄▄▃▁▁525524524514514514513508508507507507507507507507507507507506506505505505501497497497494487487487486486484484484482460459NA457NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding 527NA521518516NA511510509NA509509508NA509509509NA508508507NA506503499NA498498490NA488488487NA485485484NA462460459NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic 526NA519516515NA510510509NA508508508NA508508508NA508507506NA506503499NA498497489NA488487487NA485484483NA460460458NANANANA
us-gaap:EarningsPerShareBasic ▄▄█▃▄▃▇▃▄▂█▃▃▃▇▂▃▂▆▂▁▂▅▂▃▁▅▂▃▁▆▂▂▁▅▂▃▁▅▁▂▂▃▁▂0.560.561.020.460.610.420.960.520.570.370.970.450.470.450.90.390.470.410.840.390.30.390.730.390.520.30.730.40.480.290.820.380.380.290.690.330.420.290.680.30.360.370.480.250.38
us-gaap:EarningsPerShareDiluted ▄▄█▃▄▃█▃▄▂█▃▃▃▇▂▃▂▆▂▁▂▅▂▃▁▅▂▃▁▆▂▂▁▅▂▃▁▅▁▂▂▃▁▂0.560.561.010.460.610.420.960.520.570.370.970.450.470.450.90.390.470.410.840.390.30.390.730.390.520.30.730.40.480.290.810.380.380.290.690.330.420.290.670.30.360.370.480.250.38
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService xel:CommercialandIndustrialCustomers,xel:RetailDistribution▁▂▇▂▆▄█▂▃125512921447129714041333147112931326NA151013321352NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService xel:OtherCustomers,xel:RetailDistribution▁▄█▃▄▆█▇▆303336323334363534NA373433NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService xel:ResidentialCustomers,xel:RetailDistribution▅▄▄▁█▄▄▁▆1042999999816123199910168441086NA9598261067NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:CommercialandIndustrialCustomers,xel:RetailDistribution,us-gaap:AllOtherSegments█▆▃▃█▆▁▁▄986698557NA649NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:CommercialandIndustrialCustomers,xel:RetailDistribution,xel:RegulatedElectric▁▂▇▄▃▃█▄▂106611201383120111401148140812061112NA144512431148NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:CommercialandIndustrialCustomers,xel:RetailDistribution,xel:RegulatedNaturalGas▅▅▁▂█▅▁▂▆18016458902551775882207NA5985195NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:OtherCustomers,xel:RetailDistribution,us-gaap:AllOtherSegments▁▁▁▁▁▁▁█▁111111121NA111NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:OtherCustomers,xel:RetailDistribution,xel:RegulatedElectric▁▄█▃▄▆█▆▆293235313233353333NA363332NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:ResidentialCustomers,xel:RetailDistribution,us-gaap:AllOtherSegments▆█▃▃▁▃▃▁▁111210109101099NA1098NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:ResidentialCustomers,xel:RetailDistribution,xel:RegulatedElectric▂▂▇▁▄▂█▂▃676661865624727664890678687NA835654685NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:ResidentialCustomers,xel:RetailDistribution,xel:RegulatedNaturalGas▅▅▁▂█▅▁▂▆355326124182495325116157390NA114163374NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService us-gaap:Product▄▃▆▁█▄▆▂▅267426542875246330402735291525452824NA2887NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService xel:OtherServices▄▂▁▁▄▂▂▃█494337375242424767NA515050NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService xel:RetailDistribution▃▃▆▁█▄▆▁▅232723242482214526682366252321722446NA250621922452NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService xel:TransmissionServices▅▁█▅▅▅▇▅▄13298151127131125143132123NA136126121NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService xel:WholesaleDistribution▃▆█▁▆▇█▆▅166189205154189202207194188NA194172181NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Product,us-gaap:AllOtherSegments██▂▂▅▅▁▁▂212117171919161617NA17NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Product,xel:RegulatedElectric▁▁▇▂▃▂█▃▂208621072652214822372190270022672182NA2677NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Product,xel:RegulatedNaturalGas▅▅▁▂█▅▁▂▆567526206298784526199262625NA193NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:OtherServices,xel:RegulatedElectric▃▁▂▂▃▃▃▅█17713111818172439NA312725NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:OtherServices,xel:RegulatedNaturalGas▆█▂▃▇▂▂▁▄323624263424252328NA202325NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:RetailDistribution,us-gaap:AllOtherSegments██▂▂▅▅▁▁▂212117171919161617NA171418NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:RetailDistribution,xel:RegulatedElectric▁▂▇▂▃▂█▃▂177118132283185618991845233319171832NA231619301865NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:RetailDistribution,xel:RegulatedNaturalGas▅▅▁▂█▅▁▂▆535490182272750502174239597NA173248569NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:TransmissionServices,xel:RegulatedElectric▅▁█▅▅▅▇▅▄13298151127131125143132123NA136126121NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments xel:WholesaleDistribution,xel:RegulatedElectric▃▆█▁▆▇█▆▅166189205154189202207194188NA194172181NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:Revenues us-gaap:ConsolidationItems us-gaap:OperatingSegments2811NANA2577314128803048265829512795301626442946279430402499277226452901251529622928286926853202NA282225782782NA27242274NANANANANANANANANANANANANA
 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,us-gaap:AllOtherSegments25NANA20222219181920191721191816211917172121161821NA171721NA1716NANANANANANANANANANANANANA
 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,xel:RegulatedElectric2203NANA2249232523002802234822702255278323382299229027992224218521702667221322242250261622972301NA259922202092NA25322037NANANANANANANANANANANANANA
 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,xel:RegulatedNaturalGas583NANA308794558227292662520214289625484221258565455216284715657236369879NA205341669NA174221NANANANANANANANANANANANANA
us-gaap:CostsAndExpenses ▄▄▃▂▇▆▄▃▅▄▂▂▅▄▃▁▃▂▂▁▇▆▂▃█2356234822552167265525412352220824712370219821852460232922132068228222042115209226112537220422872708NA215721762328223420031868219722242180207823892244206019822403NANANANA
us-gaap:OperatingIncomeLoss ▃▃▇▃▄▂▆▃▄▃█▃▄▃█▃▄▃▇▃▂▂▆▃▄▂▆▃▃▁▇▃▂▂▆▂▃▂▅▂▃▂▃▁▂455450758410486339696450480426818459486465827431489441785422350391665397493325665402454316720405380344651359426322568325403353465279370
us-gaap:InterestExpense ███▇▇▅▅▅▅▄▄▄▄▄▄▄▃▃▃▂▂▂▁▁▁199195199189189177177175171165167164165161165162156153152144144144143139139NA144146139144153151151152148146144147144141143NANANANA
us-gaap:InterestAndDebtExpense █▇█▇▇▅▅▅▄▄▄▄▄▄▄▄▃▃▃▂▂▂▁▁▁189185192179179164164164160155157156158154158156150146145138138136133129129NA135136130133143144145145141138136139138134136NANANANA
us-gaap:OtherNonoperatingIncomeExpense ▁▆█▆▇▃▂▄▅█▇▆▇▅▅▅▇▅▅▅▆▅▅▅▆-112824-6-7-218526101401030103NA0031003020412710NANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▂▂▇▂▃▁▆▃▃▂█▃▃▃█▂▃▃█▂▁▂▆▂▄289299599262340208564319350307696329355337696301369319665306235284564299396NA557295355210600284259219531243315208478212NANANANANA
us-gaap:IncomeTaxExpenseBenefit ▁▁▃▂▂▁▃▃▃▅▇▄▄▄█▄▅▄█▄▄▄▇▄▅-67722425-67354591182041021161092381041281102391098387195104135NA19398118702021017578193841127116676121NANANANA
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedDefinedBenefitPlansAdjustment▄▄▄000NA000NANANANANANANANANA000000000NA00-2NANANANANANANANANANANANANANANANA
 us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:StatementEquityComponents us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome,us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges▁▁▁▁▁█▁▁00000200NA0000000000000000NA00-1NANANANANANANANANANANANANANANANA
us-gaap:IncomeTaxesPaidNet ▆▁▆█▆▄▆0-106-1540-311NANA-1-453000-53-7004-620040NANANA-173041-214-59-34970NANANANA
us-gaap:ComprehensiveIncomeNetOfTax ▄▄█▂▄▂█▃▄▂█▂▃▂▇▂▃▂▆▂▁▂▅▂▃288293520230312209494267292190494229241222459198242202428198153190369196262NA366198235137390148210127308159204134313136168NANANANA
us-gaap:NetIncomeLoss ▄▄█▃▄▂▇▃▄▂▇▃▃▃▇▂▃▂▆▂▁▂▅▂▃▁▅▂▃▁▆▂▂▁▅▁▂▁▄▁▂295292527238315214491265291189492227239227457196241209426196152196368195261150364196236140398183183140338158203136312139167NANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments us-gaap:ElectricityUsRegulated▁▂█227256550NA234180514NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments us-gaap:NaturalGasUsRegulated█▆▁9168-1NA105579NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▄▄█▃▄▂▇▃▄▂▇▂▃▂▇▂▃▂▆▂▁▂▅▂▃295292527238315214491265291189492227239227457196241209426196152196368195261NA364196236140398183183140338158203136312139NANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:Assets ███▇▇▆▆▆▆▆▅▅▅▅▅▅▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁5113350448502404858447850459874483544240431594303042468418604128541155403243949039069390533802937268368783695735363347173419833907331263226631587311403105729820294532949728537280032746627387NANANA25305NANANA
us-gaap:LiabilitiesAndStockholdersEquity ███▇▇▆▆▆▆▆▅▅▅▅▅▅▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁5113350448502404858447850459874483544240431594303042468418604128541155403243949039069390533802937268368783695735363347173419833907331263226631587311403105729820294532949728537280032746627387NANANA25305NANANA
us-gaap:StockholdersEquity ███▇▆▆▆▅▅▅▅▅▄▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▁▁13302132391314112366123291222212165116501156111455114391112311070110201098710703106711060010544102691021410214101549920974795659547930091558874NANANANANANANANANANANANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:AssetsCurrent ▄▅█▄▄▅▄▅▃▄▄▃▂▃▅▂▃▄▆▅▅▇▅▅▅▆▅▃▂▂▇▂▁▄▃▁▁▃29833113360029392909309430033056278229732898275626332842307627042732291033443048305733643196312331293218312028182704262533702560254229822861247825142732NANANA2976NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▃▃█▄▁▂▂▃▂▁▂▁▁▁▄▁▁▁▄▂▂▁▂▁▂▁▁▁▁▁▇▁▁▁▂▁▁▁▂▁▁▁2442488643539414721333211683167617384353761018440413513379137991321071015811282747639960194101941082237485115NANANA
us-gaap:AccountsReceivableNetCurrent ▅▅▅▃█▆▅▄▆▄▄▃▄▄▃▂▃▃▃▂▅▅▃▃▆▃▄▃▄▃▂▁▃▃▃▂839837821737974860856808868797807759781776754689729724741676826826760742885744786719789718704645718753752679NA718NANANANANANANA
us-gaap:InventoryNet ▃▅▅▃▁▅▄▄▃▇▇▅▄▇▇▄▄▇█▄▃▆█▃▁▆▇▃▁▄▅▂▂▇▇▃▁▅488544544483445548528511492610616542519604614526520608644532505597634501436576604494447535562473474618608484442560NANANA566NANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent ▅▄▄▃▄▂▂▃▄▃▂▂▂▂▁▁▂▂▂▂▂▃▇▇█▆▆▇▆▃▃▄▄▁▄▄230185193175191154157164188183143135145138122126154155142141155171270270295252236264246171174195192121191186NA193NANANANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:PropertyPlantAndEquipmentGross ██▇▇▇▇▆▆▆▆▆▅▅▅▅▅▅▅▄▄▄▄▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁5716155844548715354552671522495103250413495804892748532478244729446832461084551944862444134317742494419284153540343396273896038386374683681036098355113507034504340093371432901325083180431435NANANA28983NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:ElectricGenerationEquipment███▇▇▇▆▆▆▆▆▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▁▁▁445444435543301430064174841472395303974539348390163906738810384123822037335369903660436464350223399633541332033212231360305623034129550290172847128285280322771727393272542643726059NA24993NANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:GasTransmissionEquipment██▇▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▄▄▄▄▃▃▂▂▂▂▂▂▂▁▁▁▁▁665365606414628961486210603659555855580055635465536553175149506550174944481847264692464342944211415640863942390338713836377437353700367635743520NA3463NANANANANANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ███▇▇▇▆▆▆▆▆▅▅▅▅▅▄▄▄▄▄▄▃▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁1673016735165491627815961156591548315479152761500014982147031457614381142181403513790135911372413543133731316813028128541274112608124621234412216120481202311852117311165811484113781122311068NANANA10776NANANA
 us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment us-gaap:PropertyPlantAndEquipmentByType us-gaap:NuclearFuel███▇▇▇▇▆▆▆▆▆▅▅▅▅▅▄▄▄▄▄▃▃▃▃▃▂▂▂▂▂▂▁▁▁256825352506247524472417238723572326229522682237221121802153212120892063203920061985195719341903187118421821179417721744172116911667164116161584NA1541NANANANANANANA
us-gaap:PropertyPlantAndEquipmentNet ██▇▇▇▇▆▆▆▆▆▅▅▅▅▅▅▅▄▄▄▄▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁4077639483387033765137114369443587935289346793432933949335433315832841322063182331433312052982829350289662875627630270702654126122253422481324219238092340123047226722235321729215132090820663NANANA18508NANANA
us-gaap:OtherAssetsNoncurrent ██▇██▄▄▄▅▅▄▄▄▄▂▁▁▂▃▃▃▃▃▃▃▄▃▃▃▃▃▃▃▃▃▃▃▃516492478490499272272273280278259255247248673832124182176174175177173170217178184177200203193192155164163168180NANANA162NANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:LiabilitiesCurrent █▅▆▆▅▅▄▅▄▄▃▄▄▃▃▃▂▄▂▃▄▄▃▂▃▃▂▁▁▂▂▄▄▃▁▁▁▁58394568502150604424446038384178412240883340369037073247345335063188405830853537377440643470305934673654283926962526293731603831370835882653263824842536NANANA3089NANANA
us-gaap:AccountsPayableCurrent ▄██▅▆▇▇▅▄▇▄▄▂▅▃▃▁▃▃▂▃▆▅▃▅█▃▄▃▃▂▂▁▃▂▃▂▄99612941258105711541237118910921027124399297386110449169218099609248308981173106196710611261965998932959885871786902837957848979NANANA1083NANANA
us-gaap:TaxesPayableCurrent █▆▆▄█▆▆▃█▆▆▄█▆▅▄▇▆▅▃▇▅▄▃▆▅▄▂▅▄▂▁▄▃▂▁▃▂553466443342555450428316544448427339544457422330525438379280480396371269461378335242415334264215359289250189312254NANANA257NANANA
us-gaap:OtherLiabilitiesCurrent ▃█▇▇▆▅▄▄▄▅▅▄▃▅▅▄▃▅▆▅▅▅▄▃▂▃▄▂▁▂▂▃▃▃▂▂▁▁379662614614549463435441429501486439393503457448392490561499463475396341333377445288253287302338348381328278248276NANANA227NANANA
us-gaap:DividendsPayableCurrent █▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁▁▁226212212209208195194193193183182182182172172172172162162162162151151151150139139139133131131131126126127127123122NANANA113NANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:LongTermDebt ██▁181121810917672NANA16209NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ▁▃▄▄▄▆▅▄▄▆▆▆▅▇▄▄▃▅▄▄▄▅▁▁▁▃▆▆▆█▃▄▃▆▄▄▄▅6227858568508389949098848841042984975964111284382581294186385885093665365064276999898897911638108268131001829828824962NANANA839NANANA
us-gaap:OtherLiabilitiesNoncurrent ▄▃▃▃▄▄▄▅▁▁▁▅▆▅███▇▇██▇▆▆▆▆▆▆▆▅▅▅▅▄▅▅▅▆196186186190212206202226143145144225235223277280285261263279286264243237244237239245250229224217219203221225226249NANANA211NANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:StockholdersEquity ███▇▆▆▆▅▅▅▅▅▄▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▁▁13302132391314112366123291222212165116501156111455114391112311070110201098710703106711060010544102691021410214101549920974795659547930091558874NANANANANANANANANANANANANANANA
us-gaap:CommonStockValue ███▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▄▃▃▂▂▂▂▂▁▁▁▁13131311131112871287128512831272127212691269126912691268126912691269126812681267126612641263126212521244124412431236121912191218121712161212121112101205NANANA1143NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ███▇▇▇▇▆▆▆▆▅▅▅▅▅▅▄▄▄▄▄▄▃▃▃▃▃▃▂▂▂▂▂▂▁▁▁54785413533650244996489348764580451044134386407940363981392436433620355235063243320932203177296129182807279725722516241324062140208920322019181217811701NANANA1419NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▁▂▁▂▂▃▃▃▃▃▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▇▅▆███-148-141-142-135-127-124-119-122-124-125-104-106-108-110-104-106-108-109-103-105-106-108-102-103-104-106-109-111-113-112-109-102-67-94-80-50-51-53NANANA-49NANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▃█▂▄▃▆▂▅▄▇▂▃▃▆▃▄▂▆▂▆▃▆▁▂6697061223541793629105655088775810755737186391000622790535980523985643964446592NANANA642432706387477481801463659367613361551NANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▁▄▂▇▇▃▇▆▇▅▇██▅▇██▂███▇██▇-1606-1214-1421-856-852-1280-841-993-872-1057-764-726-747-1055-762-749-694-1483-708-692-738-882-703-730-800NANANA-713-723-653-557-399-586-571-465-624-1285-586-474-460NANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities █▂▇▆▃▆▁▆▃▄▂▄▃▄▃▃▂▆▃▄▂▄▂▄▄933-1087095746585-33465918213-2041401914639101-79628-3171-193180-222250233NANANA101-374630133-39-28-1379-49802122101-121NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▃▃█▂▄▃▆▂▅▄▇▂▃▃▆▃▄▂▆▂▆▃▆▁▂6697061223541793629105655088775810755737186391000622790535980523985643964446592NANANA642432706387477481801463659367613361551NANANANA
us-gaap:NetIncomeLoss ▄▄█▃▄▂▇▃▄▂▇▃▃▃▇▂▃▂▆▂▁▂▅▂▃▁▅▂▃▁▆▂▂▁▅▁▂▁▄▁▂295292527238315214491265291189492227239227457196241209426196152196368195261150364196236140398183183140338158203136312139167NANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments us-gaap:ElectricityUsRegulated▁▂█227256550NA234180514NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments us-gaap:NaturalGasUsRegulated█▆▁9168-1NA105579NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▄▄█▃▄▂▇▃▄▂▇▂▃▂▇▂▃▂▆▂▁▂▅▂▃295292527238315214491265291189492227239227457196241209426196152196368195261NA364196236140398183183140338158203136312139NANANANANA
us-gaap:IncreaseDecreaseInInventories ▄▅▇▆▂▇▆▅▂▄▇▅▂▄▇▅▂▄▇▅▂▄█▆▁-33248559-841026417-118-67422-88-7886-88-3611227-92-3713265-140NANANA-87-2789-1-14310-28-42118-34-76-11113NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▁▄▂▇▇▃▇▆▇▅▇██▅▇██▂███▇██▇-1606-1214-1421-856-852-1280-841-993-872-1057-764-726-747-1055-762-749-694-1483-708-692-738-882-703-730-800NANANA-713-723-653-557-399-586-571-465-624-1285-586-474-460NANANANA
us-gaap:PaymentsToAcquireInvestments █▅▁▃▄▄▂▃▃▇▆▃▃▂▂▃▂▅▂835523-1618330535912718218572560319517215670210109484133NANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities █▂▇▆▃▆▁▆▃▄▂▄▃▄▃▃▂▆▃▄▂▄▂▄▄933-1087095746585-33465918213-2041401914639101-79628-3171-193180-222250233NANANA101-374630133-39-28-1379-49802122101-121NANANANA
us-gaap:ProceedsFromIssuanceOfLongTermDebt ▁▇█▄▃▃▂█▁▂▇▃▁▆▃▄▅▁▆▆▁▁▁▄▃098311184273922941951186095102839407912955907470785841000542295NANANA4949815801100068800395494NANANANANANA
us-gaap:RepaymentsOfLongTermDebt ▁▆▁▁▅▂▄▁▁▁█▃▁▅▁▆▁▁▃▁▁▁▁▃▁0550-10400151300100779250045505790025000002750NANANA25164965110110210359174025NANANANA
us-gaap:PaymentsOfDividends ████▆▆▆▆▅▆▆▆▅▅▅▅▄▃▃▃▂▂▂▂▁204204200200187186185184175182182182172172172172162154154153144143143142132NANANA124124124119119123119116115109109106105NANANANA
us-gaap:PaymentsOfDividends ████▆▆▆▆▅▆▆▆▅▅▅▅▄▃▃▃▂▂▂▂▁204204200200187186185184175182182182172172172172162154154153144143143142132NANANA124124124119119123119116115109109106105NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:RepaymentsOfLongTermDebt ▁▆▁▁▅▂▄▁▁▁█▃▁▅▁▆▁▁▃▁▁▁▁▃▁0550-10400151300100779250045505790025000002750NANANA25164965110110210359174025NANANANA

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value131313111311128712871285128312721272126912691269126912681269126912691268126812671266126412631262125212441244124312361219121912181217121612121211121012051143
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.62.62.62.62.72.82.92.92.92.93.03.03.13.13.13.23.33.23.33.43.43.43.63.63.73.73.83.93.93.93.94.14.14.14.24.34.44.44.5

Common Stock Par Or Stated Value Per Share

Shares Issued

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-06-292018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-312009-12-31
Value525524514514514514513508508508507507507507507507507507507507506506505505505501497497497494487487487486486482457
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-312008-12-31
Value525524524514514514513508508507507507507507507507507507507506506505505505501497497497494487487487486486484484484482460459457453
Percentage of CommonStockSharesOutstanding100.0100.0101.8100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.00.00.0100.00.0

Common Stock Shares Authorized

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value527521518516511510509509509508509509509508508507506503499498498490488488487485485484462460459
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value526519516515510510509508508508508508508508507506506503499498497489488487487485484483460460458
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.560.561.020.460.610.420.960.520.570.370.970.450.470.450.90.390.470.410.840.390.30.390.730.390.520.30.730.40.480.290.820.380.380.290.690.330.420.290.680.30.360.370.480.250.38
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.560.561.010.460.610.420.960.520.570.370.970.450.470.450.90.390.470.410.840.390.30.390.730.390.520.30.730.40.480.290.810.380.380.290.690.330.420.290.670.30.360.370.480.250.38
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

Income Loss From Continuing Operations Per Diluted Share

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:MajorCustomers, us-gaap:ProductOrService

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

xel:CommercialandIndustrialCustomers, xel:RetailDistribution



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value125512921447129714041333147112931326151013321352
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue44.646.248.050.344.746.348.348.644.950.152.448.2
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:CommercialandIndustrialCustomers xel:RetailDistribution0.00.00.00.00.00.00.00.00.00.00.00.0

xel:OtherCustomers, xel:RetailDistribution



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value303336323334363534373433
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.42.62.52.52.42.62.42.72.62.52.62.4
Percentage of RegulatedAndUnregulatedOperatingRevenue1.11.21.21.21.11.21.21.31.21.21.31.2
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherCustomers xel:RetailDistribution0.00.00.00.00.00.00.00.00.00.00.00.0

xel:ResidentialCustomers, xel:RetailDistribution



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value10429999998161231999101684410869598261067
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax83.077.369.062.987.774.969.165.381.963.562.078.9
Percentage of RegulatedAndUnregulatedOperatingRevenue37.135.733.231.739.234.733.331.836.831.832.538.1
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:ResidentialCustomers xel:RetailDistribution0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MajorCustomers, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

xel:CommercialandIndustrialCustomers, xel:RetailDistribution, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value986698557649
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.70.60.40.50.60.60.30.40.50.40.30.7
Percentage of RegulatedAndUnregulatedOperatingRevenue0.30.30.20.20.30.30.20.20.20.20.20.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:CommercialandIndustrialCustomers xel:RetailDistribution us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.0

xel:CommercialandIndustrialCustomers, xel:RetailDistribution, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value106611201383120111401148140812061112144512431148
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax84.986.795.692.681.286.195.793.383.995.793.384.9
Percentage of RegulatedAndUnregulatedOperatingRevenue37.940.045.946.636.339.946.245.437.747.948.940.9
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:CommercialandIndustrialCustomers xel:RetailDistribution xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:CommercialandIndustrialCustomers, xel:RetailDistribution, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value180164589025517758822075985195
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.312.74.06.918.213.33.96.315.63.96.414.4
Percentage of RegulatedAndUnregulatedOperatingRevenue6.45.91.93.58.16.11.93.17.02.03.37.0
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:CommercialandIndustrialCustomers xel:RetailDistribution xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.00.00.0

xel:OtherCustomers, xel:RetailDistribution, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value111111121111
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.10.10.10.10.10.20.10.10.10.1
Percentage of RegulatedAndUnregulatedOperatingRevenue0.00.00.00.00.00.00.00.10.00.00.00.0
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherCustomers xel:RetailDistribution us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.0

xel:OtherCustomers, xel:RetailDistribution, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value293235313233353333363332
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.32.52.42.42.32.52.42.62.52.42.52.4
Percentage of RegulatedAndUnregulatedOperatingRevenue1.01.11.21.21.01.11.11.21.11.21.31.1
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherCustomers xel:RetailDistribution xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:ResidentialCustomers, xel:RetailDistribution, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value1112101091010991098
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.90.90.70.80.60.80.70.70.70.70.70.6
Percentage of RegulatedAndUnregulatedOperatingRevenue0.40.40.30.40.30.30.30.30.30.30.40.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:ResidentialCustomers xel:RetailDistribution us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.0

xel:ResidentialCustomers, xel:RetailDistribution, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value676661865624727664890678687835654685
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.951.259.848.151.849.860.552.451.855.349.150.7
Percentage of RegulatedAndUnregulatedOperatingRevenue24.023.628.724.223.123.129.225.523.327.725.724.4
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:ResidentialCustomers xel:RetailDistribution xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:ResidentialCustomers, xel:RetailDistribution, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value355326124182495325116157390114163374
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax28.325.28.614.035.324.47.912.129.47.512.227.7
Percentage of RegulatedAndUnregulatedOperatingRevenue12.611.74.17.115.811.33.85.913.23.86.413.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:ResidentialCustomers xel:RetailDistribution xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProductOrService

us-gaap:Product



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value2674265428752463304027352915254528242887
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax213.1205.4198.7189.9216.5205.2198.2196.8213.0191.2
Percentage of RegulatedAndUnregulatedOperatingRevenue95.194.995.495.696.895.095.695.795.795.7
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:Product0.00.00.00.00.00.00.00.00.00.0

xel:OtherServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value494337375242424767515050
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.93.32.62.93.73.22.93.65.13.43.83.7
Percentage of RegulatedAndUnregulatedOperatingRevenue1.71.51.21.41.71.51.41.82.31.72.01.8
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherServices0.00.00.00.00.00.00.00.00.00.00.00.0

xel:RetailDistribution



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value232723242482214526682366252321722446250621922452
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax185.4179.9171.5165.4190.0177.5171.5168.0184.5166.0164.6181.4
Percentage of RegulatedAndUnregulatedOperatingRevenue82.883.182.483.284.982.282.881.782.983.186.387.4
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:RetailDistribution0.00.00.00.00.00.00.00.00.00.00.00.0

xel:TransmissionServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value13298151127131125143132123136126121
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.57.610.49.89.39.49.710.29.39.09.58.9
Percentage of RegulatedAndUnregulatedOperatingRevenue4.73.55.04.94.24.34.75.04.24.55.04.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:TransmissionServices0.00.00.00.00.00.00.00.00.00.00.00.0

xel:WholesaleDistribution



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value166189205154189202207194188194172181
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.214.614.211.913.515.214.115.014.212.812.913.4
Percentage of RegulatedAndUnregulatedOperatingRevenue5.96.86.86.06.07.06.87.36.46.46.86.5
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:WholesaleDistribution0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:Product, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value21211717191916161717
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.71.61.21.31.41.41.11.21.31.1
Percentage of RegulatedAndUnregulatedOperatingRevenue0.70.80.60.70.60.70.50.60.60.6
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:Product us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.0

us-gaap:Product, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value2086210726522148223721902700226721822677
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax166.2163.1183.3165.6159.3164.3183.5175.3164.6177.3
Percentage of RegulatedAndUnregulatedOperatingRevenue74.275.388.083.471.276.088.685.373.988.7
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:Product xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.0

us-gaap:Product, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value567526206298784526199262625193
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax45.240.714.223.055.839.513.520.347.112.8
Percentage of RegulatedAndUnregulatedOperatingRevenue20.218.86.811.625.018.36.59.921.26.4
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:Product xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.0

xel:OtherServices, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value17713111818172439312725
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.40.50.90.81.31.41.21.92.92.12.01.8
Percentage of RegulatedAndUnregulatedOperatingRevenue0.60.30.40.40.60.60.60.91.31.01.10.9
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherServices xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:OtherServices, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value323624263424252328202325
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.52.81.72.02.41.81.71.82.11.31.71.8
Percentage of RegulatedAndUnregulatedOperatingRevenue1.11.30.81.01.10.80.80.90.90.70.90.9
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:OtherServices xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.00.00.0

xel:RetailDistribution, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value212117171919161617171418
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.71.61.21.31.41.41.11.21.31.11.11.3
Percentage of RegulatedAndUnregulatedOperatingRevenue0.70.80.60.70.60.70.50.60.60.60.60.6
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:RetailDistribution us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.0

xel:RetailDistribution, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value177118132283185618991845233319171832231619301865
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax141.1140.3157.8143.1135.3138.4158.6148.3138.2153.4144.9137.9
Percentage of RegulatedAndUnregulatedOperatingRevenue63.064.875.872.060.564.176.572.162.176.876.066.5
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:RetailDistribution xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:RetailDistribution, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value535490182272750502174239597173248569
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax42.637.912.621.053.437.711.818.545.011.518.642.1
Percentage of RegulatedAndUnregulatedOperatingRevenue19.017.56.010.623.917.45.79.020.25.79.820.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:RetailDistribution xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.00.00.0

xel:TransmissionServices, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value13298151127131125143132123136126121
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax10.57.610.49.89.39.49.710.29.39.09.58.9
Percentage of RegulatedAndUnregulatedOperatingRevenue4.73.55.04.94.24.34.75.04.24.55.04.3
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:TransmissionServices xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

xel:WholesaleDistribution, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value166189205154189202207194188194172181
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.214.614.211.913.515.214.115.014.212.812.913.4
Percentage of RegulatedAndUnregulatedOperatingRevenue5.96.86.86.06.07.06.87.36.46.46.86.5
Percentage of RegulatedAndUnregulatedOperatingRevenue xel:WholesaleDistribution xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.0

Revenue From Contract With Customer Including Assessed Tax

Revenues

us-gaap:ConsolidationItems

us-gaap:Revenues

us-gaap:OperatingSegments



Period End2020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value2811257731412880304826582951279530162644294627943040249927722645290125152962292828692685320228222578278227242274
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0104.1105.1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:OperatingSegments100.00.0100.00.00.00.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, us-gaap:AllOtherSegments



Period End2020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value25202222191819201917211918162119171721211618211717211716
Percentage of Revenues0.90.80.70.80.60.70.60.70.60.60.70.70.60.70.80.70.60.70.70.70.60.70.70.60.70.80.60.7
Percentage of RegulatedAndUnregulatedOperatingRevenue0.90.80.70.80.60.70.60.70.60.70.80.70.60.70.80.70.60.70.70.70.60.70.70.60.70.80.60.7
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:OperatingSegments us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, xel:RegulatedElectric



Period End2020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value2203224923252300280223482270225527832338229922902799222421852170266722132224225026162297230125992220209225322037
Percentage of Revenues78.487.374.079.991.988.376.980.792.388.478.082.092.189.078.882.091.988.075.176.891.285.671.992.186.175.293.089.6
Percentage of RegulatedAndUnregulatedOperatingRevenue78.487.374.079.991.988.376.980.792.392.082.082.092.189.078.882.091.988.075.176.891.285.671.992.186.175.293.089.6
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:OperatingSegments xel:RegulatedElectric0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, xel:RegulatedNaturalGas



Period End2020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value583308794558227292662520214289625484221258565455216284715657236369879205341669174221
Percentage of Revenues20.712.025.319.47.411.022.418.67.111.021.217.37.310.420.417.27.411.324.222.48.213.727.57.313.324.16.49.7
Percentage of RegulatedAndUnregulatedOperatingRevenue20.712.025.319.47.411.022.418.67.111.422.317.37.310.420.417.27.411.324.222.48.213.727.57.313.324.16.49.7
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:OperatingSegments xel:RegulatedNaturalGas0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Cost Of Goods And Services Sold

Operating Expenses

Costs And Expenses

us-gaap:CostsAndExpenses



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2356234822552167265525412352220824712370219821852460232922132068228222042115209226112537220422872708215721762328223420031868219722242180207823892244206019822403
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue83.883.974.884.184.588.277.283.183.784.872.986.087.783.372.882.782.383.372.983.288.286.676.885.284.676.484.483.787.673.682.285.386.677.085.384.987.478.485.985.6

Operating Income Loss

us-gaap:OperatingIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value455450758410486339696450480426818459486465827431489441785422350391665397493325665402454316720405380344651359426322568325403353465279370
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue16.216.125.215.915.511.822.816.916.315.227.118.117.316.727.217.317.716.727.116.811.813.423.214.815.411.923.615.616.312.426.417.814.713.423.014.715.112.621.614.114.413.520.113.913.8

Interest Expense

us-gaap:InterestExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-05-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1991951991891891771771751711651671641651611651621561531521441441441431391391446146139144153151151152148146144147144141143
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue7.17.06.67.36.06.15.86.65.85.95.66.55.95.85.56.55.65.85.35.74.94.95.05.24.35.10.05.75.05.65.66.75.95.95.26.05.15.75.56.15.1

Interest And Debt Expense

us-gaap:InterestAndDebtExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value189185192179179164164164160155157156158154158156150146145138138136133129129135136130133143144145145141138136139138134136
Percentage of InterestAndDebtExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue6.76.66.46.95.75.75.46.25.45.65.26.25.75.55.26.35.45.55.05.54.74.64.64.84.04.85.34.75.25.36.35.65.75.05.74.95.45.35.84.8

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-112824-6-7-2185261014010301030031003020412710
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-0.40.10.30.10.1-0.2-0.2-0.10.00.30.20.10.20.10.00.10.2-0.00.10.00.10.00.00.00.1-0.00.00.10.00.00.00.10.00.10.00.20.01.00.10.0

Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value289299599262340208564319350307696329355337696301369319665306235284564299396557295355210600284259219531243315208478212
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.310.719.910.210.87.218.512.011.911.023.113.012.712.122.912.013.312.122.912.28.09.719.711.212.419.811.512.88.222.112.510.18.518.810.011.28.118.29.2

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-67722425-6735459118204102116109238104128110239109838719510413519398118702021017578193841127116676121
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-0.20.32.40.90.8-0.22.42.02.04.26.84.04.23.97.84.24.64.28.24.42.83.06.83.94.26.93.84.32.77.44.52.93.16.83.54.02.86.33.34.3

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value00000000000000000-2
Percentage of IncomeTaxExpenseBenefit-0.00.00.00.0-0.00.0-0.4-0.5-0.2-0.5-0.7-0.6-0.3-0.5-0.4-0.4-0.7-2.1
Percentage of RegulatedAndUnregulatedOperatingRevenue0.00.00.00.00.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value00000200000000000000000000-1
Percentage of IncomeTaxExpenseBenefit-0.00.00.00.00.0-33.30.00.0-0.3-0.3-0.5-0.5-0.5-0.2-0.6-0.5-0.5-0.2-0.3-0.5-0.4-0.2-0.4-0.3-0.1-0.5-1.2
Percentage of RegulatedAndUnregulatedOperatingRevenue0.00.00.00.00.00.10.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Taxes Paid Net

us-gaap:IncomeTaxesPaidNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0-106-1540-311-1-453000-53-7004-620040-173041-214-59-34970
Percentage of IncomeTaxesPaidNet0.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue0.0-3.8-0.02.10.0-1.10.0-0.1-1.50.20.0-0.00.0-2.2-0.3-0.00.00.2-2.1-0.00.00.20.0-0.60.10.00.20.0-0.10.10.2-2.1-1.30.40.30.0

Profit Loss

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value288293520230312209494267292190494229241222459198242202428198153190369196262366198235137390148210127308159204134313136168
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.210.517.38.99.97.316.210.09.96.816.49.08.67.915.17.98.77.714.87.95.26.512.97.38.213.07.78.55.414.36.58.25.010.96.57.35.211.95.96.0

Net Income Loss

us-gaap:NetIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value295292527238315214491265291189492227239227457196241209426196152196368195261150364196236140398183183140338158203136312139167
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.510.417.59.210.07.416.110.09.96.816.38.98.58.115.17.98.77.914.77.85.16.712.87.38.25.512.97.68.55.514.68.07.15.511.96.57.25.311.96.16.0

us-gaap:StatementBusinessSegments

us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-23-32-22-34-24-23-32-26-22-55-12-13-17-15-16-20-15-11-7-11-1253-5-1-30-20-2
Percentage of NetIncomeLoss-7.8-11.0-4.2-14.3-7.6-10.7-6.5-9.8-7.6-29.6-2.6-5.9-7.4-6.8-3.6-10.5-6.3-5.7-1.7-5.7-8.32.91.1-3.0-0.6-2.1-0.1-10.3-1.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-0.8-1.1-0.7-1.3-0.8-0.8-1.0-1.0-0.7-2.0-0.4-0.5-0.6-0.6-0.5-0.8-0.6-0.4-0.3-0.4-0.40.20.1-0.2-0.0-0.1-0.0-0.8-0.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricityUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value227256550234180514
Percentage of NetIncomeLoss76.987.7104.474.384.1104.7
Percentage of RegulatedAndUnregulatedOperatingRevenue8.19.118.37.46.216.9
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:ElectricityUsRegulated0.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value9168-1105579
Percentage of NetIncomeLoss30.823.3-0.233.326.61.8
Percentage of RegulatedAndUnregulatedOperatingRevenue3.22.4-0.03.32.00.3
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:NaturalGasUsRegulated0.00.00.00.00.00.0

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value295292527238315214491265291189492227239227457196241209426196152196368195261364196236140398183183140338158203136312139
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.2100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.510.417.59.210.07.416.110.09.96.816.38.98.58.115.17.98.77.914.77.85.16.712.87.38.212.97.68.55.514.68.07.15.511.96.57.25.311.96.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Basic

Net Income Loss Available To Common Stockholders Diluted

Assets

us-gaap:Assets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value511335044850240485844785045987448354424043159430304246841860412854115540324394903906939053380293726836878369573536334717341983390733126322663158731140310572982029453294972853728003274662738725305
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value511335044850240485844785045987448354424043159430304246841860412854115540324394903906939053380293726836878369573536334717341983390733126322663158731140310572982029453294972853728003274662738725305
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value13302132391314112366123291222212165116501156111455114391112311070110201098710703106711060010544102691021410214101549920974795659547930091558874
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.026.226.225.525.826.627.126.326.826.626.926.626.826.827.227.127.327.127.727.627.727.628.728.628.528.228.828.829.028.5

us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-60-61-59-60-61-64-63-650-67-56-57-58-59-53-53-54-55-47-48-49-50
Percentage of StockholdersEquity-0.5-0.5-0.4-0.5-0.5-0.5-0.5-0.6-0.0-0.6-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5
Percentage of Assets-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.2-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-88-80-83-75-66-60-56-570-58-48-49-50-51-52-52-53-54-55-56-57-57
Percentage of StockholdersEquity-0.7-0.6-0.6-0.6-0.5-0.5-0.5-0.5-0.0-0.5-0.4-0.4-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.6-0.6
Percentage of Assets-0.2-0.2-0.2-0.2-0.1-0.1-0.1-0.1-0.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.2-0.2-0.2
Percentage of Assets us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-148-141-142-135-127-124-119-1220-125-104-106-108-110-104-106-108-109-103-105-106-108
Percentage of StockholdersEquity-1.1-1.1-1.1-1.1-1.0-1.0-1.0-1.0-0.0-1.1-0.9-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.1
Percentage of Assets-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.0-0.3-0.2-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value298331133600293929093094300330562782297328982756263328423076270427322910334430483057336431963123312932183120281827042625337025602542298228612478251427322976
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.86.27.26.06.16.76.76.96.46.96.86.66.46.97.66.87.07.58.88.28.39.19.09.09.29.59.48.78.68.410.98.68.610.110.08.99.210.011.8

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value244248864353941472133321168316761738435376101844041351337913799132107101581128274763996019410194108223748511525957
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.50.51.70.70.20.30.50.80.30.20.40.10.20.20.90.20.30.21.10.40.40.20.40.30.40.30.30.20.40.32.40.20.30.20.70.40.30.40.00.00.00.50.00.0

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value839837821737974860856808868797807759781776754689729724741676826826760742885744786719789718704645718753752679718
Percentage 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
Percentage of Assets1.61.71.61.52.01.91.91.82.01.91.91.81.91.91.91.71.91.91.91.82.22.22.12.12.62.22.42.22.52.32.32.22.42.62.62.42.6

Receivables Net Current

Inventory Net

us-gaap:InventoryNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value488544544483445548528511492610616542519604614526520608644532505597634501436576604494447535562473474618608484442560566
Percentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.01.11.11.00.91.21.21.21.11.41.51.31.31.51.51.31.31.61.71.41.41.61.81.41.31.71.81.51.41.71.81.61.62.12.11.71.62.02.2

Other Assets Current

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value230185193175191154157164188183143135145138122126154155142141155171270270295252236264246171174195192121191186193
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.40.40.40.40.30.40.40.40.40.30.30.40.30.30.30.40.40.40.40.40.50.80.80.90.70.70.80.80.60.60.70.70.40.70.70.7

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value571615584454871535455267152249510325041349580489274853247824472944683246108455194486244413431774249441928415354034339627389603838637468368103609835511350703450434009337143290132508318043143528983
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets111.8110.7109.2110.2110.1113.6113.8114.0114.9113.7114.3114.2114.6113.8114.3115.3114.8113.7113.5114.0113.7112.4114.1114.1113.9113.2113.1114.1114.3114.0112.9115.7115.5114.3115.3116.1115.8114.8114.5

us-gaap:PropertyPlantAndEquipmentByType

us-gaap:ConstructionInProgress



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value2756232926291745228720913029265823392087186115711596137318441687148612561679209220102005236425022672237123912298213617571681148413151085116911431186
Percentage of PropertyPlantAndEquipmentGross4.84.24.83.34.34.05.95.34.74.33.83.33.42.94.03.73.32.83.94.94.84.85.96.36.96.26.46.25.94.94.84.33.93.23.63.53.8
Percentage of Assets5.44.65.23.64.84.56.86.05.44.94.43.83.93.34.64.33.83.24.45.65.55.46.77.27.87.07.27.16.85.65.45.04.53.74.14.14.3
Percentage of Assets us-gaap:ConstructionInProgress0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricGenerationEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value44544443554330143006417484147239530397453934839016390673881038412382203733536990366043646435022339963354133203321223136030562303412955029017284712828528032277172739327254264372605924993
Percentage of PropertyPlantAndEquipmentGross77.979.478.980.379.379.477.578.879.479.780.581.281.281.681.081.381.682.181.180.080.079.979.679.178.479.078.978.878.979.679.980.380.580.880.480.279.5
Percentage of Assets87.187.986.288.587.290.288.289.891.290.792.092.793.092.992.693.793.793.492.191.291.089.890.890.389.489.589.289.990.190.890.392.993.092.492.693.191.3
Percentage of Assets us-gaap:ElectricGenerationEquipment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:GasTransmissionEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value6653656064146289614862106036595558555800556354655365531751495065501749444818472646924643429442114156408639423903387138363774373537003676357435203463
Percentage of PropertyPlantAndEquipmentGross11.611.711.711.711.711.911.811.811.811.911.511.411.311.411.211.111.211.111.211.111.211.210.610.610.710.610.510.610.710.810.810.810.910.910.910.811.0
Percentage of Assets13.013.012.812.912.813.513.513.513.613.513.113.113.012.912.812.812.812.712.712.712.712.612.112.112.212.111.912.112.312.312.212.512.612.512.512.612.6
Percentage of Assets us-gaap:GasTransmissionEquipment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NuclearFuel



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value2913290928872859285127712717271227012697266826602652257124692461245024472414240523962347225022002193218621572142210820902075208720621939192819681837
Percentage of PropertyPlantAndEquipmentGross5.15.25.35.35.45.35.35.45.45.55.55.65.65.55.45.45.55.55.65.75.75.75.65.65.65.75.85.85.85.95.96.16.15.85.96.15.8
Percentage of Assets5.75.85.75.96.06.06.16.16.36.36.36.46.46.26.16.26.36.36.46.56.56.46.46.36.46.46.56.66.76.76.77.07.06.66.87.06.7
Percentage of Assets us-gaap:NuclearFuel0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherCapitalizedPropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value2991234122512215218221542100204520272013202819591897188817411746172017091615162316191611148314671477148514671475147814801476145414841546153615861555
Percentage of PropertyPlantAndEquipmentGross5.24.24.14.14.14.14.14.14.14.14.24.14.04.03.83.83.83.83.73.83.93.93.73.73.83.93.94.04.14.24.24.24.44.64.74.94.9
Percentage of Assets5.84.64.54.64.64.74.74.64.74.74.84.74.64.64.34.44.44.44.24.44.44.44.24.24.34.44.44.64.74.84.84.95.05.25.45.75.7
Percentage of Assets us-gaap:OtherCapitalizedPropertyPlantAndEquipment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

xel:PlantToBeRetired



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value217259276290306322337101111111722313629343842556471778592101115115141152105112115151182199236
Percentage of PropertyPlantAndEquipmentGross0.40.50.50.50.60.60.70.00.00.00.00.00.00.10.10.10.10.10.10.10.20.20.20.20.20.30.30.30.40.40.30.30.30.40.60.60.8
Percentage of Assets0.40.50.50.60.60.70.80.00.00.00.00.00.10.10.10.10.10.10.10.10.20.20.20.20.30.30.30.40.40.50.30.40.40.50.60.70.9
Percentage of Assets xel:PlantToBeRetired0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value167301673516549162781596115659154831547915276150001498214703145761438114218140351379013591137241354313373131681302812854127411260812462123441221612048120231185211731116581148411378112231106810776
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets32.733.232.933.533.434.134.535.035.434.935.335.135.334.935.335.535.334.836.136.336.335.636.837.037.337.237.638.338.738.738.739.739.839.540.240.640.940.442.6

us-gaap:PropertyPlantAndEquipmentByType

us-gaap:NuclearFuel



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value2568253525062475244724172387235723262295226822372211218021532121208920632039200619851957193419031871184218211794177217441721169116671641161615841541
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment15.315.115.115.215.315.415.415.215.215.315.115.215.215.215.115.115.215.214.914.814.814.914.914.814.714.614.614.514.514.514.314.314.214.114.113.913.9
Percentage of Assets5.05.05.05.15.15.35.35.35.45.35.35.35.45.35.35.45.35.35.45.45.45.35.55.55.55.45.55.65.65.65.55.75.75.65.75.75.6
Percentage of Assets us-gaap:NuclearFuel0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value407763948338703376513711436944358793528934679343293394933543331583284132206318233143331205298282935028966287562763027070265412612225342248132421923809234012304722672223532172921513209082066318508
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets79.778.377.077.577.680.380.079.880.479.879.980.180.379.879.980.680.579.978.478.878.577.878.178.077.677.076.576.976.776.575.377.377.075.876.176.876.175.473.1

Deferred Tax Assets Liabilities Net

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value516492478490499272272273280278259255247248673832124182176174175177173170217178184177200203193192155164163168180162
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.01.01.01.01.00.60.60.60.60.60.60.60.60.60.20.10.10.30.50.50.50.50.50.50.50.60.50.60.60.60.70.60.70.50.60.60.60.70.6

Liabilities Current

us-gaap:LiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value583945685021506044244460383841784122408833403690370732473453350631884058308535373774406434703059346736542839269625262937316038313708358826532638248425363089
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.49.110.010.49.29.78.69.49.69.57.98.89.07.98.68.98.210.48.19.510.211.09.88.810.110.88.68.48.09.410.212.812.612.29.39.49.09.312.2

Long Term Debt Current

Accounts Payable Current

us-gaap:AccountsPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value996129412581057115412371189109210271243992973861104491692180996092483089811731061967106112619659989329598858717869028379578489791083
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.92.62.52.22.42.72.72.52.42.92.32.32.12.52.32.32.12.52.42.22.43.23.02.83.13.72.93.13.03.12.82.92.73.12.93.43.13.64.3

Taxes Payable Current

us-gaap:TaxesPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value553466443342555450428316544448427339544457422330525438379280480396371269461378335242415334264215359289250189312254257
Percentage of TaxesPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.10.90.90.71.21.01.00.71.31.01.00.81.31.11.00.81.31.11.00.81.31.11.10.81.31.11.00.81.31.10.90.71.21.00.90.71.10.91.0

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value379662614614549463435441429501486439393503457448392490561499463475396341333377445288253287302338348381328278248276227
Percentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.71.31.21.31.11.01.01.01.01.21.11.11.01.21.11.11.01.31.51.31.31.31.11.01.01.11.30.90.80.91.01.11.21.31.21.00.91.00.9

Dividends Payable Current

us-gaap:DividendsPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value226212212209208195194193193183182182182172172172172162162162162151151151150139139139133131131131126126127127123122113
Percentage of DividendsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.40.50.40.40.4

Liabilities Noncurrent

Long Term Debt

us-gaap:LongTermDebt



Period End2020-03-312019-12-312019-09-302018-12-31
Value18112181091767216209
Percentage of LongTermDebt100.0100.0100.0100.0
Percentage of Assets35.435.935.235.2

Long Term Debt Noncurrent

Deferred Tax Liabilities Noncurrent

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value6227858568508389949098848841042984975964111284382581294186385885093665365064276999898897911638108268131001829828824962839
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.21.61.71.71.82.22.02.02.02.42.32.32.32.72.12.12.12.42.32.32.32.51.81.91.92.33.03.13.13.72.62.82.83.42.93.03.03.53.3

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value196186186190212206202226143145144225235223277280285261263279286264243237244237239245250229224217219203221225226249211
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.40.40.40.40.40.50.50.30.30.30.50.60.50.70.70.70.70.70.80.80.70.70.70.70.70.70.80.80.70.70.70.70.70.80.80.80.90.8

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value13302132391314112366123291222212165116501156111455114391112311070110201098710703106711060010544102691021410214101549920974795659547930091558874
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.026.226.225.525.826.627.126.326.826.626.926.626.826.827.227.127.327.127.727.627.727.628.728.628.528.228.828.829.028.5

us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-60-61-59-60-61-64-63-650-67-56-57-58-59-53-53-54-55-47-48-49-50
Percentage of StockholdersEquity-0.5-0.5-0.4-0.5-0.5-0.5-0.5-0.6-0.0-0.6-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5
Percentage of Assets-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.2-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-88-80-83-75-66-60-56-570-58-48-49-50-51-52-52-53-54-55-56-57-57
Percentage of StockholdersEquity-0.7-0.6-0.6-0.6-0.5-0.5-0.5-0.5-0.0-0.5-0.4-0.4-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.5-0.6-0.6
Percentage of Assets-0.2-0.2-0.2-0.2-0.1-0.1-0.1-0.1-0.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.2-0.2-0.2
Percentage of Assets us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value-148-141-142-135-127-124-119-1220-125-104-106-108-110-104-106-108-109-103-105-106-108
Percentage of StockholdersEquity-1.1-1.1-1.1-1.1-1.0-1.0-1.0-1.0-0.0-1.1-0.9-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.1
Percentage of Assets-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.0-0.3-0.2-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value131313111311128712871285128312721272126912691269126912681269126912691268126812671266126412631262125212441244124312361219121912181217121612121211121012051143
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.62.62.62.62.72.82.92.92.92.93.03.03.13.13.13.23.33.23.33.43.43.43.63.63.73.73.83.93.93.93.94.14.14.14.24.34.44.44.5

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value547854135336502449964893487645804510441343864079403639813924364336203552350632433209322031772961291828072797257225162413240621402089203220191812178117011419
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.710.710.610.310.410.610.910.410.410.310.39.79.89.79.79.29.39.19.28.78.78.79.08.58.58.38.48.08.07.87.77.27.16.97.16.56.56.25.6

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-148-141-142-135-127-124-119-122-124-125-104-106-108-110-104-106-108-109-103-105-106-108-102-103-104-106-109-111-113-112-109-102-67-94-80-50-51-53-49
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.2-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.4-0.4-0.4-0.3-0.2-0.3-0.3-0.2-0.2-0.2-0.2

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6697061223541793629105655088775810755737186391000622790535980523985643964446592642432706387477481801463659367613361551
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue23.825.240.621.025.221.834.620.730.127.135.622.625.622.932.924.928.520.333.820.833.322.033.616.618.523.117.025.917.018.518.728.319.023.414.323.315.719.6

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1606-1214-1421-856-852-1280-841-993-872-1057-764-726-747-1055-762-749-694-1483-708-692-738-882-703-730-800-713-723-653-557-399-586-571-465-624-1285-586-474-460
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-57.1-43.4-47.2-33.2-27.1-44.4-27.6-37.4-29.5-37.8-25.3-28.6-26.7-37.8-25.1-30.0-25.0-56.1-24.4-27.5-24.9-30.1-24.5-27.2-25.0-25.6-28.4-24.0-24.5-15.5-22.8-20.2-19.1-22.2-50.1-22.3-20.6-16.4

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value933-1087095746585-33465918213-2041401914639101-79628-3171-193180-222250233101-374630133-39-28-1379-49802122101-121
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue33.2-3.923.522.30.220.3-11.024.80.67.6-6.85.50.75.31.34.1-2.923.7-0.16.8-6.56.2-7.89.37.33.6-14.723.15.9-1.5-1.1-4.90.4-1.731.34.74.4-4.3

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6697061223541793629105655088775810755737186391000622790535980523985643964446592642432706387477481801463659367613361551
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue23.825.240.621.025.221.834.620.730.127.135.622.625.622.932.924.928.520.333.820.833.322.033.616.618.523.117.025.917.018.518.728.319.023.414.323.315.719.6

Net Income Loss

us-gaap:NetIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value295292527238315214491265291189492227239227457196241209426196152196368195261150364196236140398183183140338158203136312139167
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.510.417.59.210.07.416.110.09.96.816.38.98.58.115.17.98.77.914.77.85.16.712.87.38.25.512.97.68.55.514.68.07.15.511.96.57.25.311.96.16.0

us-gaap:StatementBusinessSegments

us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-23-32-22-34-24-23-32-26-22-55-12-13-17-15-16-20-15-11-7-11-1253-5-1-30-20-2
Percentage of NetIncomeLoss-7.8-11.0-4.2-14.3-7.6-10.7-6.5-9.8-7.6-29.6-2.6-5.9-7.4-6.8-3.6-10.5-6.3-5.7-1.7-5.7-8.32.91.1-3.0-0.6-2.1-0.1-10.3-1.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-0.8-1.1-0.7-1.3-0.8-0.8-1.0-1.0-0.7-2.0-0.4-0.5-0.6-0.6-0.5-0.8-0.6-0.4-0.3-0.4-0.40.20.1-0.2-0.0-0.1-0.0-0.8-0.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:AllOtherSegments0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricityUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value227256550234180514
Percentage of NetIncomeLoss76.987.7104.474.384.1104.7
Percentage of RegulatedAndUnregulatedOperatingRevenue8.19.118.37.46.216.9
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:ElectricityUsRegulated0.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value9168-1105579
Percentage of NetIncomeLoss30.823.3-0.233.326.61.8
Percentage of RegulatedAndUnregulatedOperatingRevenue3.22.4-0.03.32.00.3
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:NaturalGasUsRegulated0.00.00.00.00.00.0

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value295292527238315214491265291189492227239227457196241209426196152196368195261364196236140398183183140338158203136312139
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.2100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue10.510.417.59.210.07.416.110.09.96.816.38.98.58.115.17.98.77.914.77.85.16.712.87.38.212.97.68.55.514.68.07.15.511.96.57.25.311.96.1
Percentage of RegulatedAndUnregulatedOperatingRevenue us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-33248559-841026417-118-67422-88-7886-88-3611227-92-3713265-140-87-2789-1-14310-28-42118-34-76-11113
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1606-1214-1421-856-852-1280-841-993-872-1057-764-726-747-1055-762-749-694-1483-708-692-738-882-703-730-800-713-723-653-557-399-586-571-465-624-1285-586-474-460
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue-57.1-43.4-47.2-33.2-27.1-44.4-27.6-37.4-29.5-37.8-25.3-28.6-26.7-37.8-25.1-30.0-25.0-56.1-24.4-27.5-24.9-30.1-24.5-27.2-25.0-25.6-28.4-24.0-24.5-15.5-22.8-20.2-19.1-22.2-50.1-22.3-20.6-16.4

Payments To Acquire Property Plant And Equipment

Payments To Acquire Investments

us-gaap:PaymentsToAcquireInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value835523-1618330535912718218572560319517215670210109484133
Percentage of PaymentsToAcquireInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value933-1087095746585-33465918213-2041401914639101-79628-3171-193180-222250233101-374630133-39-28-1379-49802122101-121
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RegulatedAndUnregulatedOperatingRevenue33.2-3.923.522.30.220.3-11.024.80.67.6-6.85.50.75.31.34.1-2.923.7-0.16.8-6.56.2-7.89.37.33.6-14.723.15.9-1.5-1.1-4.90.4-1.731.34.74.4-4.3

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value0983111842739229419511860951028394079129559074707858410005422954949815801100068800395494
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0550-1040015130010077925004550579002500000275025164965110110210359174025
Percentage of RepaymentsOfLongTermDebt0.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Payments Of Dividends

us-gaap:PaymentsOfDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value204204200200187186185184175182182182172172172172162154154153144143143142132124124124119119123119116115109109106105
Percentage of PaymentsOfDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments Of Dividends

us-gaap:PaymentsOfDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value204204200200187186185184175182182182172172172172162154154153144143143142132124124124119119123119116115109109106105
Percentage of PaymentsOfDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments For Repurchase Of Common Stock

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0550-1040015130010077925004550579002500000275025164965110110210359174025
Percentage of RepaymentsOfLongTermDebt0.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Debt Instrument Interest Rate Stated Percentage

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.021-0.0160.120.0920.074-0.0259999999999999950.1290.1690.1690.0140000000000000120.2940.310.329
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period

Share Based Compensation

us-gaap:ShareBasedCompensation



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2611121619201546121213171151113158111015555863133131110981097
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Liabilities

Deferred Tax Assets Net

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value46444340383738344039421371351331301241221207673706640373541413937343732333435404040304230
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value126016721718176316190
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.00.0

Cash And Cash Equivalents Period Increase Decrease

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents



Period End2020-03-312019-12-312019-03-312018-12-31
Value24424894147
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0

Proceeds From Repayments Of Short Term Debt

us-gaap:ProceedsFromRepaymentsOfShortTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1170-338-664345214601-244-343211300-27017921326-81264-663782-387-518-50322-80126-177298-177142120169-60612465426-89-3377
Percentage of ProceedsFromRepaymentsOfShortTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-8876-7987-8867-9130656186126761012109998101012108995
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-71087-51087-8978-994656186126761012109998101012108995
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue87.5125.0114.3116.771.4111.1100.0100.0100.0103.8117.8110.492.371.6458.7100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1-2-1-1-2-10000-1003-3
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue12.5-25.0-14.3-16.728.6-11.10.00.0-0.0-3.8-17.8-10.47.728.4-358.7

us-gaap:AllowanceForFundsUsedDuringConstructionInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2322152020293026232023161415171413151512122023232119181515131211131316131213
Percentage of AllowanceForFundsUsedDuringConstructionInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value284111666238606621241146354718532-31591923778-3323991021529025659-4450224115411611282627
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect



Period End2020-03-312019-03-31
Value-4-53
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0

us-gaap:StatementEquityComponents

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:CommonStock



Period End2020-03-312019-09-302019-03-312018-09-30
Value0.430.4050.410.38
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0

us-gaap:DebtRelatedCommitmentFeesAndDebtIssuanceCosts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value77666766665556666665555556125566666655555
Percentage of DebtRelatedCommitmentFeesAndDebtIssuanceCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxExpenseBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value341383212634745159138191115193107226921601062371088213619686150130671621101677719182114881547694
Percentage of DeferredIncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1-1-1-1-1-2-2-2-2-1-1-1-10-1
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-25-21-22-22-22-28-27-27-27-26-26-26-26-23-24
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses2500.02100.02200.02200.02200.01400.01350.01350.01350.01360.31595.22600.02600.02460.92411.9

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-2-2-3-3-3-3-3-3-3-2-2-3-3-2-2
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1-2-1-1-1-2-1-1-1000000
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit50.0100.033.333.333.366.733.333.333.322.616.5-0.0-0.018.817.9

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value555557666666666
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value525151515152525252525252525252
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets1040.01020.01020.01020.01020.0742.9866.7866.7866.7796.6850.0866.7866.7835.9841.3

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value556666555656666
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value313736363633333333363636363940
Percentage of DefinedBenefitPlanInterestCost620.0740.0600.0600.0600.0550.0660.0660.0660.0610.0613.3600.0600.0621.8613.3

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value00-1-1-100-1-100-1-1-10
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost0.00.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value293028292938403031483030303130
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost0.00.0-2800.0-2900.0-2900.00.00.0-3000.0-3100.0-5447.1-4327.2-3000.0-3000.0-2769.8-3188.4

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.01000000.00.00.00.01000000.01000000.01000000.01000000.0605000.0465000.01000000.01000000.0705000.0432000.0
Percentage of DefinedBenefitPlanServiceCost0.0100.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value242222222223242424232324242322
Percentage of DefinedBenefitPlanServiceCost0.02200.00.00.00.02300.02400.02400.02400.03861.05063.92400.02400.03290.15310.2

us-gaap:DepreciationAmortizationAndAccretionNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value466453451443438446444382387381375369368336332326323301284279277266259259250253236243231233198246238224210226215206
Percentage of DepreciationAmortizationAndAccretionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:DerivativeGainLossOnDerivativeNet

xel:CommodityTradingContract, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value1-3151052311510101-1-3430-15-2
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:NaturalGasCommodity, us-gaap:Nondesignated



Period End2020-03-312019-03-31
Value-6-3
Percentage of DerivativeGainLossOnDerivativeNet-600.0-300.0

us-gaap:HedgingDesignation

us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-5-615-2-2521015-3-310-4-3-3412-8-15-7
Percentage of DerivativeGainLossOnDerivativeNet-500.0200.0100.0100.0-200.00.0100.0100.033.30.1100.0100.0-306.6563.299.7105.2-397.9271.6111.7100.0331.72085.7112.6111.2335.3

us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

us-gaap:InterestRateContract, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value-2-1-1-1-1-1-1-10-1-1-1-1-1-1-1-1-100000
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value-2-1-1-1-1-1-1-10-1-1-1-1-1-1-1-1-100000
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet100.0100.0100.0100.0100.0100.0100.0100.0102.299.399.6100.0103.0103.1103.2103.8102.9103.0102.9102.8100.698.398.2

us-gaap:DividendsCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value227213214209210196195195194184184183183173173173173163163163163152152151150140140134132132131127127126126122-815116117112
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value227213214209210196195195194184184183183173173173173163163163163152152151150140140134132132131127127126126122-815116117112
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.210.00.210.210.210.00.210.210.210.00.350.350.35
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.015-0.0060.012-0.0160.009-0.011-0.014-0.0160.02-0.04-0.026-0.015
Percentage of EffectiveIncomeTaxRateReconciliationOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-0.0090.027999999999999997-0.017-0.006-0.0270.033-0.07-0.011-0.0140.0140.0
Percentage of EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.049-0.00100000000000000090.050.050.050.00.050.0510.049-0.00200000000000000180.0410.0410.04
Percentage of EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCredits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.1720.0129999999999999980.0610.1190.0860.0090000000000000010.0260.0540.060.00200000000000000180.0480.0450.04
Percentage of EffectiveIncomeTaxRateReconciliationTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentDividendsOrDistributions



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1110101010109998811111111111110999999898160888888877
Percentage of EquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings

us-gaap:CommodityContract



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value6117-18-10-2200600000001011600400
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationGainLossIncludedInEarnings100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases

us-gaap:CommodityContract



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value122534410345110763202910057585120190510
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements

us-gaap:CommodityContract



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1816211611819201221332219283314181220171938203353149812
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1110109910996777799913108877777777777777777777
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-75983-2361145737-60712848-2145364-3941965-150010917-1421407271124-515246-585-4661-10480-7
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayable



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-20144101-1614533841-42110-1569-121672249-22-315-33-99102-8-110-375175825-20296-114104-7294-56-27-199
Percentage of IncreaseDecreaseInAccountsPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInEmployeeRelatedLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-157316-145-4584-146168-14851210-11812-36-8510310-125-181-2-1211-180-14-42-134-53-2-4-2
Percentage of IncreaseDecreaseInEmployeeRelatedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherCurrentAssets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value31-2216-523334-13-38-155-14877619-11-861663-3-12-5685-6-3466510-31-1071-2-11295-4321-61
Percentage of IncreaseDecreaseInOtherCurrentAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value-778595-159-369789-230-177378-147-429688-119-445152-12634122144-1301207882-1351710684-8355993
Percentage of IncreaseDecreaseInOtherCurrentLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1016031128-153-59-214-147-102816-1723300-34131316-146-33-98-630-88-41148-61-14-92-591749-112126
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToContingentlyIssuableShares



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value001110000000000000000000
Percentage of IncrementalCommonSharesAttributableToContingentlyIssuableShares100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestPaidNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value20715420015419014217813218112718712617413016712916411715810516110515598152153127155124156126138116150-919135121132
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShortTermDebtType

us-gaap:LineOfCreditFacilityInterestRateDuringPeriod

us-gaap:CommercialPaper



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value0.02050.02620.02830.02680.02450.02420.01930.01630.0150.01280.00970.00750.00770.00720.00730.00560.00460.00480.00460.00360.0033
Percentage of LineOfCreditFacilityInterestRateDuringPeriod100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0-2012-4-200-30
Percentage of OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax0.0100.00.0100.0100.0100.0100.00.00.0100.00.0

us-gaap:OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0-1001-1-100-20
Percentage of OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax0.0100.00.00.0100.0100.0100.00.00.0100.00.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value11013411400010000000000011000
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value00001110300000000000000000200
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax0.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value0-2012-4-20-300-7000-7000-7000000
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax0.0100.00.0100.0100.0100.0100.00.0100.00.00.0100.00.00.0100.0100.00.00.00.0100.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value-102-9-10-7-500000000000000000000
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax0.0-100.00.0-1000.0-350.0125.0-0.00.01.60.00.00.00.00.00.60.40.00.00.01.70.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-100-9-5-9-2-300-7000-700
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax0.0-0.00.0-250.0225.0100.0101.70.00.0100.00.00.0100.6100.50.00.0

us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1-2113-12101000-6000-7000-6000110
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value-83-8-9-6-41100100000000000000000
Percentage of OtherComprehensiveIncomeLossNetOfTax-800.0-150.0-800.0-900.0-200.0400.050.0100.00.030.7102.286.787.0-13.9108.9109.6442.7-13.075.170.065.5-7.160.968.364.047.657.345.7

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-71-7-3-53201111-5111-611
Percentage of OtherComprehensiveIncomeLossNetOfTax-700.0-50.0-700.0-100.0500.0150.0200.0100.0130.6202.2186.8187.086.1208.9209.6542.787.1175.0170.1

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-71-7-8-3-53211111-5111-6111-6111110-3-7-3426-13-2901
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-71-7-8-3-53211111-5111-6111-6111110-3-7-3426-13-2901
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value-2-1-1-1-1-1-1-10000000000000000000000
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value100000000000000000000000000-100
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax100.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax

us-gaap:InterestRateContract, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-09-30
Value-133-12-13-9-700
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.00.00.0

us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-09-30
Value-133-12-13-9-700
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.00.00.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-102-9-10-7-500000000000000000000000-8-3525-7-300000-40
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-30-3-3-2-200000000000000000000000-5-2316-4-2000
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax100.00.0100.0100.0100.0100.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value0.0-1000000.00.01000000.0-1000000.0-1000000.0
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax-0.00.0-0.0-50.050.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value-31-3-2-20
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax100.00.0100.0100.0100.00.0

us-gaap:OtherCostOfOperatingRevenue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value912910109988888810888988109879778875787688847
Percentage of OtherCostOfOperatingRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherOperatingActivitiesCashFlowStatement



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value14-791356-22-55-10-5-100-200000-1000
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.00.00.00.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-6-39263-19-23100500-1100-122001230-1120-15
Percentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireProductiveAssets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value16071207132984584411978571020883106278272474910697737127001496708707770898725753822752764702606497601481581540655594486481
Percentage of PaymentsToAcquireProductiveAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:ShareIssuanceProgram

us-gaap:ProceedsFromIssuanceOfCommonStock

xel:DividendReinvestmentProgram



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value10109910
Percentage of ProceedsFromIssuanceOfCommonStock100.0100.0100.0100.0100.0

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-330-32-131-31-18000-18000-12
Percentage of ProceedsFromPaymentsForOtherFinancingActivities100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.00.00.0100.0

us-gaap:ProceedsFromSaleAndMaturityOfOtherInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value830513-1617830035412217817972059818216715165158104482117
Percentage of ProceedsFromSaleAndMaturityOfOtherInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value23221520202930262320231614151714131515121220232321212219181515131211131316131213
Percentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

us-gaap:InterestRateSwap, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value2111-1-511
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value211111
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0-100.0-20.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value1010-1-3-4-10-4000000000000000-1-10
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax50.00.0100.00.0100.060.0-400.0-100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value000002-1-100000000000000000000
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax0.00.00.00.0-0.0-40.0-100.0-100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value101117-5-20-4-1-1-1-1-1-1-1-1-1-1
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax50.00.0100.0-100.0-340.0-500.0-200.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodTax

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value00005-2-1060003000300
Percentage of ReclassificationFromAociCurrentPeriodTax0.00.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RegulatedAndUnregulatedOperatingRevenue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value281127983013257731412880304826582951279630162540280427943040249927722645290125152962292828692685320227302822257827822551272422742578256828312438281625662628230728072618231420162695
Percentage of RegulatedAndUnregulatedOperatingRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination



Period End2020-03-312019-12-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-30
Value0-1-1-100000000000000-1-1-1-1-3-10000
Percentage of RegulatedAndUnregulatedOperatingRevenue0.0-0.0-0.0-0.00.00.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1-0.1-0.0-0.0-0.0-0.0

us-gaap:OperatingSegments



Period End2020-03-312019-12-312019-03-312018-12-312018-03-31
Value28112799314228812951
Percentage of RegulatedAndUnregulatedOperatingRevenue100.0100.0100.0100.0100.0

us-gaap:RegulatedOperatingRevenueGas



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value583544222794558227
Percentage of RegulatedOperatingRevenueGas100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IntersegmentElimination, us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-03-312018-12-31
Value0.01000000.01000000.01000000.0
Percentage of RegulatedOperatingRevenueGas0.00.20.10.2

us-gaap:OperatingSegments, us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value583544222794558227
Percentage of RegulatedOperatingRevenueGas100.0100.0100.0100.0100.0100.0

us-gaap:ProductOrService

us-gaap:RevenueNotFromContractWithCustomer

xel:AlternativeandOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value137144138114101145133113127130
Percentage of RevenueNotFromContractWithCustomer100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

xel:AlternativeandOther, us-gaap:AllOtherSegments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value4333333222
Percentage of RevenueNotFromContractWithCustomer2.92.12.22.63.02.12.31.81.61.5

xel:AlternativeandOther, xel:RegulatedElectric



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value117123119101881101028188107
Percentage of RevenueNotFromContractWithCustomer85.485.486.288.687.175.976.771.769.382.3

xel:AlternativeandOther, xel:RegulatedNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value16181610103228303721
Percentage of RevenueNotFromContractWithCustomer11.712.511.68.89.922.121.126.529.116.2

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0125-12518416590000
Percentage of RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability0.0100.0100.0100.0100.00.00.00.00.0

us-gaap:ShortTermDebtType

us-gaap:ShorttermDebtAverageOutstandingAmount

us-gaap:CommercialPaper



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value1404130313131186500634102810005606797785572904774047742902727801076802730
Percentage of ShorttermDebtAverageOutstandingAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShortTermDebtType

us-gaap:ShorttermDebtMaximumAmountOutstandingDuringPeriod

us-gaap:CommercialPaper



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value208017801597140310388241349119781486712477195826098411183846478107213601021894
Percentage of ShorttermDebtMaximumAmountOutstandingDuringPeriod100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssued1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-03-312011-12-31
Value181714151715171520746111145713816141913141418161816
Percentage of StockIssued1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesNewIssues

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value00900040000000000000000330260001100122001
Percentage of StockIssuedDuringPeriodSharesNewIssues100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueNewIssues



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value121046210123520810170005000-29910399120639741689995399964588812
Percentage of StockIssuedDuringPeriodValueNewIssues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value101043810103319710140003000-398909911155867151888236881403778
Percentage of StockIssuedDuringPeriodValueNewIssues83.3100.094.8100.083.394.394.7100.082.4-1324.30.00.069.70.00.0100.0138.593.291.892.727.792.292.091.887.591.691.589.991.091.490.644.590.389.689.526.587.986.888.166.3

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value20240221103000100010002009706160002310455114
Percentage of StockIssuedDuringPeriodValueNewIssues16.70.05.20.016.75.75.30.017.61424.30.00.030.30.0100.0-0.0-38.56.88.27.372.37.88.08.212.58.48.510.19.08.69.455.59.710.410.573.512.113.211.933.7

us-gaap:TaxesExcludingIncomeAndExciseTaxes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value149140137142150139135137145134133134142131117138145122123129136106117116124105102113103100991059689929687818181
Percentage of TaxesExcludingIncomeAndExciseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrealizedGainOnSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value454871353553-150534543
Percentage of UnrealizedGainOnSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrealizedLossOnSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value88-16701523-1518
Percentage of UnrealizedLossOnSecurities100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense



Period End2020-03-31
Value0.0
Percentage of UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense0.0

us-gaap:UnregulatedOperatingRevenue



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value252420222219
Percentage of UnregulatedOperatingRevenue100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, us-gaap:AllOtherSegments



Period End2020-03-312019-09-302019-03-312018-09-30
Value25202219
Percentage of UnregulatedOperatingRevenue100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseDepreciationAndAmortization



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value463446447439433443440377383376371365365332328322320296280274273262255255245228243248231239226228194242229224219221211
Percentage of UtilitiesOperatingExpenseDepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value579574580586597623593578557596541578586562590596577583565594585620568585560575562529599531534510565532532510550509516
Percentage of UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:ConservationandDemandSideManagementProgramExpenses



Period End2020-03-312019-03-31
Value7472
Percentage of ConservationandDemandSideManagementProgramExpenses100.0100.0

xel:CostofnaturalGasSoldandTransported



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value2852725547930658
Percentage of CostofnaturalGasSoldandTransported100.0100.0100.0100.0100.0100.0

xel:CreditLossesTopic326ASCTopic326



Period End2020-03-31
Value2
Percentage of CreditLossesTopic326ASCTopic326100.0

us-gaap:RetirementPlanType

xel:DefinedBenefitPlanCreditsNotRecognizedDueToEffectsofRegulation

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-30
Value1000000.00.01000000.00.01000000.0
Percentage of DefinedBenefitPlanCreditsNotRecognizedDueToEffectsofRegulation100.00.0100.00.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-30
Value2011-50
Percentage of DefinedBenefitPlanCreditsNotRecognizedDueToEffectsofRegulation200.00.0100.00.0-5000.0

us-gaap:RetirementPlanType

xel:DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-10-1-1-1-1-1-1-100-1-1-10
Percentage of DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2733282828629031311153434343434
Percentage of DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments-2700.00.0-2800.0-2800.0-2800.0-6200.0-9000.0-3100.0-3100.0-13097.5-4838.5-3400.0-3400.0-2980.5-3606.5

us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

xel:DerivativeInstrumentsGainLossReclassifiedToRegulatoryAssetsAndLiabilitiesNet

xel:NaturalGasCommodityforElectricGeneration, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-12-312015-12-312015-09-30
Value0.00.00.00.00.00.00.00.0-1000000.00.00.0900000.0-200000.0-600000.0-400000.0
Percentage of DerivativeInstrumentsGainLossReclassifiedToRegulatoryAssetsAndLiabilitiesNet0.00.00.00.00.00.00.00.0100.00.00.0100.0100.0100.0100.0

xel:EffectiveIncomeTaxRateReconciliationOtherRegulatoryItemsPercent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.0840.07200000000000001-0.056-0.055-0.057-0.003-0.006-0.01-0.010.0-0.008-0.009-0.005
Percentage of EffectiveIncomeTaxRateReconciliationOtherRegulatoryItemsPercent100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

xel:ElectricFuelandPurchasedPower



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value7978319529149471040
Percentage of ElectricFuelandPurchasedPower100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk

xel:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityNetLossesGainsRecognizedAsRegulatoryAssetsAndLiabilities

us-gaap:CommodityContract



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value12210-11-20022-7-9293518331503-11-2411-17-113440-33
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLiabilityNetLossesGainsRecognizedAsRegulatoryAssetsAndLiabilities100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:IncreaseDecreaseinAccruedUnbilledRevenues



Period End2020-03-312019-03-31
Value-149-92
Percentage of IncreaseDecreaseinAccruedUnbilledRevenues100.0100.0

xel:Inventorytransferstoplantpropertyandequipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value332424221855391916
Percentage of Inventorytransferstoplantpropertyandequipment100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:NuclearFuelAmortization



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3330312731303031312630263027313225233320282231312827232923262531182527282325
Percentage of NuclearFuelAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

xel:Pretaxgainslossesreclassifiedintoincomeduringtheperiodfromregulatoryassetsandliabilities

xel:ElectricCommodityContract, us-gaap:Nondesignated



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value4-10-1103-3532338-2-16-8
Percentage of Pretaxgainslossesreclassifiedintoincomeduringtheperiodfromregulatoryassetsandliabilities100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:NaturalGasCommodity, us-gaap:Nondesignated



Period End2020-03-312019-03-31
Value51
Percentage of Pretaxgainslossesreclassifiedintoincomeduringtheperiodfromregulatoryassetsandliabilities125.0-100.0

us-gaap:HedgingDesignation

us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value12100903-5332234-2-16-20
Percentage of Pretaxgainslossesreclassifiedintoincomeduringtheperiodfromregulatoryassetsandliabilities25.00.0-100.00.0-0.0900.00.0100.0166.765.4100.0100.073.191.6100.0100.0235.2

xel:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value10107101013131111910776765676689
Percentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:RegulatedOperatingRevenueElectric



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value220322302771232523002802
Percentage of RegulatedOperatingRevenueElectric100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, us-gaap:ElectricityUsRegulated



Period End2020-03-312019-12-312019-09-302019-03-312018-12-312018-09-30
Value220322302771232523002802
Percentage of RegulatedOperatingRevenueElectric100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

xel:RevenuesIncludingIntersegmentRevenues

us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-03-312018-12-31
Value583545795559
Percentage of RevenuesIncludingIntersegmentRevenues100.0100.0100.0100.0

us-gaap:AccountsReceivableGrossCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value8978928757861030915909856921849859808832827802735778776793726882884814793939797838766839769753698776811806730773
Percentage of AccountsReceivableGrossCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

us-gaap:AccrualForEnvironmentalLossContingenciesGross

xel:AshlandMgpSite, xel:NSPWisconsin



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value2223222627
Percentage of AccrualForEnvironmentalLossContingenciesGross100.0100.0100.0100.0100.0

us-gaap:AccumulatedDeferredInvestmentTaxCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value484950515254545657585960616364656768697072737476777979808182838485868889919299
Percentage of AccumulatedDeferredInvestmentTaxCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdditionalPaidInCapitalCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value6659665666366190617361686125592059035898588858815872588158985896588958895873586358445837581557995681561956155595551553535334531652985327528052615229
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value585554495655534853525149515048464951515055575450545351475051495357585451525456
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:AlternativeInvestment

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:CommingledFunds, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-06-302019-03-312018-12-312017-12-31
Value843935988937819659
Percentage of AlternativeInvestment100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-06-302019-03-312018-12-312018-09-302017-12-31
Value843935988937819704659
Percentage of AlternativeInvestment100.0100.0100.0100.0100.00.0100.0

us-gaap:AssetRetirementObligationsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value273427012679264725992568257225342504247528832849281527822703267126392608255025172476244619221897183818151785176217411719171616951662165112931277985969881
Percentage of AssetRetirementObligationsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value73827867
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value74747268
Percentage of AssetsFairValueDisclosure101.490.292.3101.5

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value73827867
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:AvailableForSaleSecurities

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:CommingledFunds, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0000079
Percentage of AvailableForSaleSecurities0.00.00.00.00.0100.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:CommingledFunds, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value756733815802774758
Percentage of AvailableForSaleSecurities0.00.00.00.00.0959.5

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:CommingledFunds, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value843935997988937898
Percentage of AvailableForSaleSecurities0.00.00.00.00.01136.7

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:DebtSecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value488495484473464436441
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:DebtSecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value131312141600
Percentage of AvailableForSaleSecuritiesDebtSecurities2.72.62.53.03.40.00.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:DebtSecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value514489489485484466438
Percentage of AvailableForSaleSecuritiesDebtSecurities105.398.8101.0102.5104.3106.999.3

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:DebtSecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value501508496487480436441
Percentage of AvailableForSaleSecuritiesDebtSecurities102.7102.6102.5103.0103.4100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:AvailableForSaleSecuritiesEquitySecurities

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquitySecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value726962800798786697791
Percentage of AvailableForSaleSecuritiesEquitySecurities100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquitySecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value1211000
Percentage of AvailableForSaleSecuritiesEquitySecurities0.10.20.10.10.00.00.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquitySecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value435485393396407401423
Percentage of AvailableForSaleSecuritiesEquitySecurities59.950.449.149.651.857.553.5

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquitySecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value727964801799786697791
Percentage of AvailableForSaleSecuritiesEquitySecurities100.1100.2100.1100.1100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashAndCashEquivalents, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value7133232724
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashEquivalents, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value17171716
Percentage of CashAndCashEquivalentsFairValueDisclosure23.951.573.966.7

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashAndCashEquivalents, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value7133232724
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashEquivalents, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value17171716
Percentage of CashAndCashEquivalentsFairValueDisclosure23.951.573.966.7

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashAndCashEquivalents, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value7133232724
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:CashEquivalents, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value17171716
Percentage of CashAndCashEquivalentsFairValueDisclosure23.951.573.966.7

us-gaap:ContractWithCustomerLiabilityNoncurrent



Period End2020-03-312019-12-31
Value202203
Percentage of ContractWithCustomerLiabilityNoncurrent100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:CreditFacility

us-gaap:DebtLongtermAndShorttermCombinedAmount

srt:ParentCompany, us-gaap:RevolvingCreditFacility



Period End2020-03-312019-09-302019-06-302019-03-312018-09-30
Value449365632327378
Percentage of DebtLongtermAndShorttermCombinedAmount100.0100.0100.0100.0100.0

us-gaap:CreditFacility

us-gaap:RevolvingCreditFacility



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value58546311288031087486724105684354279862141138547521287510351910301080768
Percentage of DebtLongtermAndShorttermCombinedAmount130.3126.8178.5245.60.0128.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CreditFacility, dei:LegalEntity

us-gaap:RevolvingCreditFacility, xel:NSPWisconsin



Period End2020-03-312019-12-312019-09-302019-06-30
Value76656850
Percentage of DebtLongtermAndShorttermCombinedAmount16.90.018.67.9

us-gaap:RevolvingCreditFacility, xel:NspMinnesota



Period End2020-03-312019-12-312019-09-302019-06-30
Value10219213
Percentage of DebtLongtermAndShorttermCombinedAmount2.20.05.233.7

us-gaap:RevolvingCreditFacility, xel:Psco



Period End2020-03-312019-12-312019-09-302019-06-30
Value899231
Percentage of DebtLongtermAndShorttermCombinedAmount1.80.02.536.6

us-gaap:RevolvingCreditFacility, xel:Sps



Period End2020-03-312019-12-312019-09-302019-06-30
Value424022
Percentage of DebtLongtermAndShorttermCombinedAmount9.40.00.50.3

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:DecommissioningTrustAssetsAmount

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302018-12-31
Value797995823800
Percentage of DecommissioningTrustAssetsAmount100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302018-12-31
Value489497485436
Percentage of DecommissioningTrustAssetsAmount61.449.958.954.5

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302018-12-31
Value1313120
Percentage of DecommissioningTrustAssetsAmount1.61.31.50.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquitySecurities, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302018-12-31
Value2142244023172055
Percentage of DecommissioningTrustAssetsAmount268.8245.2281.5256.9

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, xel:NuclearDecommissioningFund



Period End2020-03-312019-12-312019-09-302018-12-31
Value1776174017201649
Percentage of DecommissioningTrustAssetsAmount222.8174.9209.0206.1

us-gaap:DeferredIncomeTaxLiabilitiesNet



Period End2020-03-312019-12-31
Value44924509
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0

us-gaap:DerivativeAssetCollateralObligationToReturnCashOffset



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value3232323232320000000000000000000000
Percentage of DerivativeAssetCollateralObligationToReturnCashOffset100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation

us-gaap:DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset

us-gaap:OtherCurrentAssets, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value635234644144151812156812209145
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherCurrentAssets, xel:ElectricCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value01110011222411334
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset0.01.92.91.60.00.06.75.616.713.342.545.215.09.633.725.669.7

us-gaap:OtherCurrentAssets, xel:NaturalGasCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value0.00.00.00.00.00.00.00.00.0135000.00.00.00.015000.031000.0303000.0
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset0.00.00.00.00.00.00.00.00.02.00.00.00.00.20.25.2

us-gaap:OtherNoncurrentAssets, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value45454140261412121577777866
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset71.486.5120.662.563.431.880.066.7125.046.7113.281.660.235.588.049.8111.8

us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentAssets, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value635335654144161914179131322121710
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset100.0101.9102.9101.6100.0100.0106.7105.6116.7113.3144.5145.5115.0109.6133.8125.9174.9

us-gaap:OtherNoncurrentAssets, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value45454140261412121577777866
Percentage of DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset71.486.5120.662.563.431.880.066.7125.046.7113.281.660.235.588.049.8111.8

us-gaap:BalanceSheetLocation

us-gaap:DerivativeAssets

us-gaap:OtherCurrentAssets



Period End2020-03-312019-12-312019-09-302018-12-31
Value45556187
Percentage of DerivativeAssets100.0100.0100.0100.0

us-gaap:OtherNoncurrentAssets



Period End2020-03-312019-12-312019-09-302018-12-31
Value39222234
Percentage of DerivativeAssets86.740.036.139.1

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentAssets, xel:PurchasedPowerAgreements, us-gaap:FairValueMeasurementsNonrecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value3334
Percentage of DerivativeAssets6.75.54.94.6

us-gaap:OtherNoncurrentAssets, xel:PurchasedPowerAgreements, us-gaap:FairValueMeasurementsNonrecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value12131416
Percentage of DerivativeAssets26.723.623.018.4

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation

us-gaap:OtherCurrentAssets, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value24262454
Percentage of DerivativeAssets53.347.339.362.1

us-gaap:OtherCurrentAssets, xel:ElectricCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value18202725
Percentage of DerivativeAssets40.036.444.328.7

us-gaap:OtherCurrentAssets, xel:NaturalGasCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value0674
Percentage of DerivativeAssets0.010.911.54.6

us-gaap:OtherNoncurrentAssets, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value259818
Percentage of DerivativeAssets55.616.413.120.7

us-gaap:OtherNoncurrentAssets, xel:ElectricCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-31
Value20
Percentage of DerivativeAssets4.40.0

us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentAssets, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value42525883
Percentage of DerivativeAssets93.394.595.195.4

us-gaap:OtherNoncurrentAssets, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value279818
Percentage of DerivativeAssets60.016.413.120.7

us-gaap:DerivativeInstrumentsAndHedges



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value4555618656877675284474782038424623334863388512015470919210059697988616454
Percentage of DerivativeInstrumentsAndHedges100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsAndHedgesLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value523873665361312730292728262625262729272619212220222326293032331115615761
Percentage of DerivativeInstrumentsAndHedgesLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsAndHedgesLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value183175178121122129107113120126131136143148154156167168173171178183187194199209217222242
Percentage of DerivativeInstrumentsAndHedgesLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsAndHedgesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value392222232534424749484950485051505551545351535359678495100111126135137146152184
Percentage of DerivativeInstrumentsAndHedgesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BalanceSheetLocation

us-gaap:DerivativeLiabilities

us-gaap:OtherCurrentLiabilities



Period End2020-03-312019-12-312019-09-302018-12-31
Value52387361
Percentage of DerivativeLiabilities100.0100.0100.0100.0

us-gaap:OtherNoncurrentLiabilities



Period End2020-03-312019-12-312019-09-302018-12-31
Value183175178129
Percentage of DerivativeLiabilities351.9460.5243.8211.5

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation

us-gaap:OtherCurrentLiabilities, us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:FairValueMeasurementsRecurring, us-gaap:DesignatedAsHedgingInstrument



Period End2020-03-312019-12-312019-09-302018-12-31
Value130407
Percentage of DerivativeLiabilities25.00.054.811.5

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentLiabilities, xel:PurchasedPowerAgreements, us-gaap:FairValueMeasurementsNonrecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value18181720
Percentage of DerivativeLiabilities34.647.423.332.8

us-gaap:OtherNoncurrentLiabilities, xel:PurchasedPowerAgreements, us-gaap:FairValueMeasurementsNonrecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value71757993
Percentage of DerivativeLiabilities136.5197.4108.2152.5

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation

us-gaap:OtherCurrentLiabilities, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value21151034
Percentage of DerivativeLiabilities40.439.513.755.7

us-gaap:OtherCurrentLiabilities, xel:NaturalGasCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value0560
Percentage of DerivativeLiabilities0.013.28.20.0

us-gaap:OtherNoncurrentLiabilities, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-31
Value1121009936
Percentage of DerivativeLiabilities215.4263.2135.659.0

us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentLiabilities, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value34205641
Percentage of DerivativeLiabilities65.452.676.767.2

us-gaap:OtherNoncurrentLiabilities, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value1121009936
Percentage of DerivativeLiabilities215.4263.2135.659.0

us-gaap:DerivativeLiabilityCollateralRightToReclaimCashOffset



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value6111213191514843334324444676376433
Percentage of DerivativeLiabilityCollateralRightToReclaimCashOffset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency, us-gaap:HedgingDesignation

us-gaap:DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset

us-gaap:OtherCurrentLiabilities, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value636346776060282213157913209146
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherCurrentLiabilities, xel:ElectricCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value0111011122411334
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset0.01.62.21.30.03.64.57.713.337.943.613.59.433.424.759.2

us-gaap:OtherCurrentLiabilities, xel:NaturalGasCommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302018-12-312017-12-312017-09-302016-09-302016-06-302015-12-31
Value0.00.00.00.00.0135000.015000.031000.0303000.0
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset0.00.00.00.00.01.80.20.24.4

us-gaap:OtherNoncurrentLiabilities, us-gaap:CommodityContract, us-gaap:FairValueMeasurementsRecurring, us-gaap:Nondesignated



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-31
Value1913108-5-17131519101010101011119
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset30.220.621.710.4-8.3-28.346.468.2146.266.7136.6113.478.051.1115.576.6141.7

us-gaap:BalanceSheetLocation, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherCurrentLiabilities, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value63644778606029231417101315221211
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset100.0101.6102.2101.3100.0100.0103.6104.5107.7113.3139.7143.9113.5109.4133.5163.6

us-gaap:OtherNoncurrentLiabilities, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value1913108-5-171315191010101010119
Percentage of DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset30.220.621.710.4-8.3-28.346.468.2146.266.7136.6113.478.051.1115.5141.7

us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeNonmonetaryNotionalAmount

xel:ElectricCommodity



Period End2020-03-312019-12-312019-09-302018-12-31
Value799512187
Percentage of DerivativeNonmonetaryNotionalAmount100.0100.0100.0100.0

xel:NaturalGasCommodity



Period End2020-03-312019-12-312019-09-302018-12-31
Value14911013092
Percentage of DerivativeNonmonetaryNotionalAmount188.6115.8107.4105.7

us-gaap:EquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value158155151145141141140138141140131133131132134133132130808181838485868787888991911009292959697
Percentage of EquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

us-gaap:NaturalGasUsRegulated



Period End2020-03-312019-12-312019-09-302018-12-31
Value158155151141
Percentage of EquityMethodInvestments100.0100.0100.0100.0

us-gaap:DerivativeInstrumentRisk

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs

us-gaap:CommodityContract



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-31
Value541528-7294864193565695172424618314617567310524414147716122
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GuaranteeObligationsMaximumExposure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-12-312012-12-312011-12-312010-12-31
Value606262585612196967155
Percentage of GuaranteeObligationsMaximumExposure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value167192166180159174158176147174147175151172155169148166143160131158132158132159134156135162160176161177162165158163159
Percentage of InterestPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentsAndOtherNoncurrentAssets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value24292731259925732504231724732398240423972300223121872091204819871917190218071880186718321816183817931755167916221663161715781522153714631476
Percentage of InvestmentsAndOtherNoncurrentAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value149821523415259151621497913502133241310112954129671311612955128101269212480121751206111903117091156611389111791023699849778977698269452926491858940870986098577789877617399
Percentage of LiabilitiesOtherThanLongtermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:CreditFacility

us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity

srt:ParentCompany, us-gaap:RevolvingCreditFacility



Period End2020-03-312019-12-312019-09-302019-06-302019-06-012019-03-312018-09-30
Value1250125012501250100010001250
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

srt:ParentCompany, xel:A364DayTermLoan, us-gaap:ShortTermDebt



Period End2020-03-312020-03-23
Value1200700
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity96.00.0

us-gaap:CreditFacility

us-gaap:RevolvingCreditFacility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value31003100310031002750325030003000325032502750275027502750275027502750275027502750275027502450
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity248.0248.0248.0248.0275.00.0240.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CreditFacility, dei:LegalEntity

us-gaap:RevolvingCreditFacility, xel:Sps



Period End2020-03-312019-12-312019-09-302019-06-302019-06-012019-03-31
Value500500500500400400
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity40.040.040.040.040.040.0

us-gaap:ShortTermDebtType

us-gaap:CommercialPaper



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312012-12-31
Value4300360036003600325032503000300032503250275027502750275027502750275027502750275027502750245024502450
Percentage of LineOfCreditFacilityMaximumBorrowingCapacity344.0288.0288.0288.0325.00.0240.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidatedEntities, us-gaap:CreditFacility

us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity

srt:ParentCompany, us-gaap:RevolvingCreditFacility



Period End2020-03-312019-09-302019-06-302019-03-312018-09-30
Value801885618673872
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

srt:ParentCompany, xel:A364DayTermLoan, us-gaap:ShortTermDebt



Period End2020-03-31
Value0.0
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity0.0

us-gaap:CreditFacility

us-gaap:RevolvingCreditFacility



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value2515263719721947216325142276219424072208195221292339236522752538187526472231172016701681
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity314.0298.0319.1289.30.0288.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CreditFacility, dei:LegalEntity

us-gaap:RevolvingCreditFacility, xel:NSPWisconsin



Period End2020-03-312019-12-312019-09-302019-06-30
Value748582100
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity9.20.09.316.2

us-gaap:RevolvingCreditFacility, xel:NspMinnesota



Period End2020-03-312019-12-312019-09-302019-06-30
Value490498481287
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity61.20.054.446.4

us-gaap:RevolvingCreditFacility, xel:Psco



Period End2020-03-312019-12-312019-09-302019-06-30
Value692691691469
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity86.40.078.175.9

us-gaap:RevolvingCreditFacility, xel:Sps



Period End2020-03-312019-12-312019-09-302019-06-30
Value458460498498
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity57.20.056.380.6

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, dei:LegalEntity

xel:BilateralCreditAgreement, us-gaap:LetterOfCredit, xel:NspMinnesota



Period End2020-03-312019-12-312019-09-302019-06-30
Value49535552
Percentage of LineOfCreditFacilityRemainingBorrowingCapacity6.10.06.28.4

us-gaap:LongTermDebtAndCapitalLeaseObligations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1701017407168191599616118158031550815311145221452014572140911369614194134021310413148124901269011896114991149911501117521120510910109141081610642101431010587068598884894509263926492637888
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1102702853553240655685645745730550575525570971065665745770725725725772822802802826258859131113091059462535455543
Percentage of LongTermDebtAndCapitalLeaseObligationsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:LongTermDebtFairValue

us-gaap:FairValueInputsLevel2



Period End2020-03-312019-12-312019-09-302018-12-31
Value19864202272006416755
Percentage of LongTermDebtFairValue100.0100.0100.0100.0

us-gaap:OperatingLeaseLiabilityCurrent



Period End2020-03-312019-12-31
Value143194
Percentage of OperatingLeaseLiabilityCurrent100.0100.0

us-gaap:OperatingLeaseLiabilityNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value116315491598164715290
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.00.0

us-gaap:OtherLongTermInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1291361321261241211221151171141111111039898995148464748454343434138383937343435343232332828
Percentage of OtherLongTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PrepaidTaxes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value684339417579717863685519617610610711518016311712111818560
Percentage of PrepaidTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesInventory

us-gaap:PublicUtilitiesInventory

us-gaap:PublicUtilitiesInventoryFuel



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-31
Value170191187164134170151147144186166156150181181164172202212203174183193168149189201186171189202182176236205188
Percentage of PublicUtilitiesInventory100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesInventoryNaturalGas



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-31
Value35838647381071105237113130634711012758491151407376169199985716117486601321458089179197176
Percentage of PublicUtilitiesInventory20.643.546.028.728.462.972.835.425.760.878.440.831.760.570.135.828.857.266.336.244.092.7103.158.738.785.486.646.435.269.971.944.250.776.196.193.4

us-gaap:PublicUtilitiesInventorySupplies



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302010-12-31
Value283270271272273271267312311311320321321312306304298290291256254244240234229225228222216213213210207202205196
Percentage of PublicUtilitiesInventory166.5141.4144.9165.9203.7159.4176.8212.2216.0167.2192.7205.1214.3171.9169.1185.3173.4143.7136.9126.0146.1133.2123.9139.2153.7118.9113.2119.7126.5112.8105.5115.3117.485.9100.3104.0

us-gaap:RegulatoryAssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value508488455425412464452440422424407375360363317325317344347364351444415462481417396396369352353366333402412381319388357
Percentage of RegulatoryAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RegulatoryAssetsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value313029353120314531803326316631772965300530113023300930802874288628972858281227592760277424882451249725092709272727112762236723592361238922242160218621511987
Percentage of RegulatoryAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RegulatoryLiabilityCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value456407469442492436410395270239256261186220228279272306365418393410379366258274208205193168219193220275309170176156199
Percentage of RegulatoryLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RegulatoryLiabilityNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value534250775082513951725187516151135141508313581386140013831367134313731332116911761185116311401107109010591052107010771059105310661107110111331143119111791148
Percentage of RegulatoryLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShortTermBorrowings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1765595933159712521038437682102581451478460539236644718384664451969101969777776575930235442560230448133921950656531466459
Percentage of ShortTermBorrowings100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

srt:ParentCompany, xel:A364DayTermLoan, us-gaap:ShortTermDebt



Period End2020-03-31
Value1200
Percentage of ShortTermBorrowings68.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, dei:LegalEntity

xel:BilateralCreditAgreement, us-gaap:LetterOfCredit, xel:NspMinnesota



Period End2020-03-312019-12-312019-09-302019-06-30
Value26222023
Percentage of ShortTermBorrowings1.53.72.11.4

us-gaap:ShortTermDebtType

us-gaap:CommercialPaper



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312012-12-31
Value17655959331597125210384376821025814514784605392366447183846644519691020697759602
Percentage of ShortTermBorrowings100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LetterOfCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value202030545149494231302814161919282929396761607147
Percentage of ShortTermBorrowings1.13.43.23.44.14.711.26.23.03.75.41.82.64.85.26.315.83.460.915.06.35.910.26.3

us-gaap:ShortTermDebtType

us-gaap:ShortTermDebtWeightedAverageInterestRate

us-gaap:CommercialPaper



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312012-12-31
Value0.01960.02340.02540.02740.0290.02970.02570.02470.02340.0190.01530.01490.01180.00950.00770.0080.00630.00820.00380.00480.00550.00560.00330.00250.0036
Percentage of ShortTermDebtWeightedAverageInterestRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value133021323913141123661232912222121651165011561114551143911123110701102010987107031067110600105441026910214102141015499209747956595479300915588748850857385378482843182348181808376057391735572836963
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value-148-141-142-135-127-124-119-122-124-125-104-106-108-110-104-106-108-109-103-105-106-108-102-103-104-106-109-111-113-112-109-102-67-94-80-50-51-53-50-52-48-49-53
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-1.1-1.1-1.1-1.1-1.0-1.0-1.0-1.0-1.1-1.1-0.9-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.0-1.1-1.0-1.0-1.1-1.1-1.2-1.2-1.2-1.3-1.2-1.2-0.8-1.1-1.0-0.6-0.6-0.7-0.7-0.7-0.7-0.7-0.8

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value6659665666366190617361686125592059035898588858815872588158985896588958895873586358445837581557995681561956155595551553535334531652985327528052615241522948174800478447694695
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest50.150.350.550.150.150.550.350.851.151.551.552.953.153.453.755.155.255.655.757.157.257.157.358.558.358.758.860.260.260.360.362.062.162.862.663.964.164.763.364.965.065.567.4

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value1313131113111287128712851283127212721269126912691269126812691269126912681268126712661264126312621252124412441243123612191219121812171216121212111210120511501149114811431134
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest9.99.910.010.410.410.510.510.911.011.111.111.411.511.511.611.911.912.012.012.312.412.412.412.712.913.013.013.413.513.713.814.214.314.314.414.714.814.915.115.515.615.716.3

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value5478541353365024499648934876458045104413438640794036398139243643362035523506324332093220317729612918280727972572251624132406214020892032201918121781170116881493147214191187
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest41.240.940.640.640.540.040.139.339.038.538.336.736.536.135.734.033.933.533.331.631.431.531.329.929.929.429.327.727.527.227.225.024.524.024.022.021.821.122.220.220.019.517.1

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:TradingSecurities

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:MutualFund, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value56656151
Percentage of TradingSecurities100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument, us-gaap:InvestmentType

us-gaap:CarryingReportedAmountFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:MutualFund, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value57575552
Percentage of TradingSecurities101.887.790.2102.0

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring, us-gaap:MutualFund, xel:RabbiTrust



Period End2020-03-312019-12-312019-09-302018-12-31
Value56656151
Percentage of TradingSecurities100.0100.0100.0100.0

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value363533302728272121202030302927262625151616167771287744444366510
Percentage of UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:AccruedUnbilledRevenues



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value561713623639662755650648605764625608555729567589525654546582544728574609575687575626586663521549491688552590550708694
Percentage of AccruedUnbilledRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

xel:Basispoints

srt:ParentCompany, xel:A364DayTermLoan, us-gaap:ShortTermDebt



Period End2020-03-23
Value60.0
Percentage of Basispoints100.0

us-gaap:Range, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, dei:LegalEntity

srt:Maximum, xel:FERCProceedingMISOROEComplaint, xel:FederalEnergyRegulatoryCommissionFERC, xel:NSPMinnesotaandNSPWisconsinMember



Period End2020-03-31
Value100.0
Percentage of Basispoints0.0

srt:Minimum, xel:FERCProceedingMISOROEComplaint, xel:FederalEnergyRegulatoryCommissionFERC, xel:NSPMinnesotaandNSPWisconsinMember



Period End2020-03-31
Value50.0
Percentage of Basispoints0.0

xel:DerivativeGrossLiabilityPositionAggregateFairValue



Period End2020-03-312019-12-312019-06-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value11760000000000000000000112232141726108655
Percentage of DerivativeGrossLiabilityPositionAggregateFairValue100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Range, xel:ShareIssuanceProgram

xel:Expectedsettlementprice

srt:Maximum, xel:ForwardEquityAgreements



Period End2020-03-312019-12-312019-03-312018-12-31
Value735740455460
Percentage of Expectedsettlementprice100.0100.0100.0100.0

srt:Minimum, xel:ForwardEquityAgreements



Period End2020-03-312019-12-312019-03-312018-12-31
Value720730450450
Percentage of Expectedsettlementprice98.098.698.997.8

us-gaap:VariableInterestEntitiesByClassificationOfEntity

xel:GeneratingCapacityUnderLongTermPurchasedPowerAgreements

us-gaap:VariableInterestEntityNotPrimaryBeneficiaryAggregatedDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value3266.03986.03986.03986.03770.03770.03540.03470.03537.03537.03537.03537.03467.03698.03698.03698.03698.03698.03698.03698.03698.03698.03338.03338.03406.03324.03324.03773.03773.03773.04101.0
Percentage of GeneratingCapacityUnderLongTermPurchasedPowerAgreements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:NetDeferredTaxLiabilityassociatedwiththeUnrecognizedTaxBenefitAmountsandRelatedNOLsandTaxCreditCarryforwards



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value-30-29-28-25-22-24-13
Percentage of NetDeferredTaxLiabilityassociatedwiththeUnrecognizedTaxBenefitAmountsandRelatedNOLsandTaxCreditCarryforwards100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsNotesLoansAndFinancingReceivablesByIndustryOfCounterpartyType, us-gaap:ConcentrationRiskByType

xel:Numberofmostsignificantcounterpartiesforwholesaletradingandnontradingcommodityactivitieswithcreditexposure

xel:MunicipalorCooperativeEntitiesorOtherUtilities, us-gaap:CreditConcentrationRisk



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value8.09.08.09.010.08.010.09.09.08.09.010.010.010.010.09.09.09.0
Percentage of Numberofmostsignificantcounterpartiesforwholesaletradingandnontradingcommodityactivitieswithcreditexposure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator

us-gaap:CreditConcentrationRisk, us-gaap:ExternalCreditRatingInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value6.06.06.06.05.06.05.04.05.04.03.02.02.01.01.01.01.02.0
Percentage of Numberofmostsignificantcounterpartiesforwholesaletradingandnontradingcommodityactivitieswithcreditexposure75.066.775.066.750.075.050.044.455.650.033.320.020.010.010.011.111.122.2

us-gaap:CreditConcentrationRisk, us-gaap:InternalInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value3.04.03.03.05.03.0
Percentage of Numberofmostsignificantcounterpartiesforwholesaletradingandnontradingcommodityactivitieswithcreditexposure37.544.437.533.350.037.5

xel:OtherAssetsExcludingPropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value737478527937799478275949595358955698572856195560549354715041496249034937485648694854483645364523452745674663463446634706428542114237416139464010404439913821
Percentage of OtherAssetsExcludingPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator

xel:PercentageOfWholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties

us-gaap:CreditConcentrationRisk, us-gaap:ExternalCreditRatingInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value0.560.60.530.360.40.430.370.290.350.290.220.120.10.060.060.060.070.09
Percentage of PercentageOfWholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CreditConcentrationRisk, us-gaap:ExternalCreditRatingNonInvestmentGrade



Period End2020-03-312019-09-302019-06-302018-06-302018-03-312017-12-312017-09-30
Value0.040.030.040.030.040.050.05
Percentage of PercentageOfWholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties7.15.711.110.311.417.222.7

us-gaap:CreditConcentrationRisk, us-gaap:InternalInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.130.140.080.110.130.09
Percentage of PercentageOfWholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties23.223.315.130.632.520.9

xel:TaxBenefitsAssociatedWithNolAndTaxCreditCarryforwards



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value424040363535363332312947454342403836393531282825232740-38363336313233333838
Percentage of TaxBenefitsAssociatedWithNolAndTaxCreditCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

xel:UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value10910101191113191922106105104103979694605653503230272832313029322829303134343419
Percentage of UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConcentrationRiskByType, xel:CreditQualityIndicator

xel:WholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties

us-gaap:CreditConcentrationRisk, us-gaap:ExternalCreditRatingInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value154154156728896695670453628241314131618
Percentage of WholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CreditConcentrationRisk, us-gaap:ExternalCreditRatingNonInvestmentGrade



Period End2020-03-312019-09-302019-06-302018-06-302018-03-312017-12-312017-09-30
Value12885778
Percentage of WholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties7.85.111.18.910.015.622.4

us-gaap:CreditConcentrationRisk, us-gaap:InternalInvestmentGrade



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value353724213020
Percentage of WholesaleTradingAndNonTradingCommodityCreditExposureForMostSignificantCounterparties22.724.015.429.234.120.8

Line plots across dimensions of each concept

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers, us-gaap:ProductOrService


us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService


us-gaap:IncomeTaxExpenseBenefit us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents


us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments


us-gaap:StockholdersEquity us-gaap:StatementEquityComponents


us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType


us-gaap:StockholdersEquity us-gaap:StatementEquityComponents


us-gaap:NetIncomeLoss us-gaap:StatementBusinessSegments