CMS


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:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

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

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
dei:LegalEntity
us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, dei:LegalEntity
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments, dei:LegalEntity
us-gaap:ProductOrService
us-gaap:ProductOrService, dei:LegalEntity
us-gaap:ProductOrService
us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostsAndExpenses

us-gaap:OperatingIncomeLoss
dei:LegalEntity

us-gaap:InterestExpense
dei:LegalEntity

us-gaap:InterestExpenseDebt
dei:LegalEntity

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
dei:LegalEntity

us-gaap:NonoperatingIncomeExpense
dei:LegalEntity

us-gaap:IncomeTaxExpenseBenefit
dei:LegalEntity

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

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity

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

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

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

us-gaap:LiabilitiesAndStockholdersEquity
dei:LegalEntity
us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquity
dei:LegalEntity

us-gaap:AssetsCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities

us-gaap:CashAndCashEquivalentsAtCarryingValue
dei:LegalEntity

us-gaap:AccountsReceivableNetCurrent
dei:LegalEntity

us-gaap:OtherAssetsCurrent
dei:LegalEntity

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
us-gaap:PublicUtility

us-gaap:PropertyPlantAndEquipmentNet
dei:LegalEntity
us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

us-gaap:OtherAssetsNoncurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:LiabilitiesCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:DebtCurrent

us-gaap:NotesPayableCurrent
dei:LegalEntity

us-gaap:LongTermDebtCurrent
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:AccountsPayableCurrent
dei:LegalEntity

us-gaap:TaxesPayableCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities

us-gaap:OtherLiabilitiesCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:RestructuringCostAndReserve, us-gaap:RestructuringPlan

us-gaap:LiabilitiesNoncurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities

us-gaap:LongTermDebtNoncurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:MinorityInterest

us-gaap:OtherLiabilitiesNoncurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquity
dei:LegalEntity

us-gaap:CommonStockValue

us-gaap:RetainedEarningsAccumulatedDeficit
cms:CumulativeEffectPeriodOfAdoption
dei:LegalEntity
us-gaap:StatementScenario, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementBusinessSegments

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInOperatingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInInvestingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInFinancingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInOperatingActivities
dei:LegalEntity

us-gaap:NetIncomeLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

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

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet
dei:LegalEntity

us-gaap:IncreaseDecreaseInInventories
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInInvestingActivities
dei:LegalEntity

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInFinancingActivities
dei:LegalEntity

us-gaap:ProceedsFromIssuanceOfLongTermDebt
dei:LegalEntity

us-gaap:RepaymentsOfLongTermDebt
dei:LegalEntity

us-gaap:RepaymentsOfLongTermDebt
dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument
us-gaap:DebtInstrumentInterestRateStatedPercentage
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:SubsequentEventType, dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateContinuingOperations
dei:LegalEntity

us-gaap:DeferredTaxLiabilities
dei:LegalEntity

us-gaap:DeferredTaxAssetsNet
dei:LegalEntity

us-gaap:UnrecognizedTaxBenefits
dei:LegalEntity

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:OperatingLeaseRightOfUseAsset
dei:LegalEntity

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
dei:LegalEntity
us-gaap:StatementEquityComponents, dei:LegalEntity
cms:AdjustmentsToAdditionalPaidInCapitalStockholderContribution
us-gaap:StatementEquityComponents
cms:CommonStockReissuedValue

cms:EffectiveIncomeTaxRateReconciliationAMTSequestrationPercent

cms:EffectiveIncomeTaxRateReconciliationRegulatoryTaxBenefits
dei:LegalEntity

cms:FinancingIncome
dei:LegalEntity
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments, dei:LegalEntity
us-gaap:SubsidiarySaleOfStock
cms:ForwardContractIndexedToIssuersEquityAggregateSalesPrice

cms:InterestAndDividendIncomeRelatedParties
dei:LegalEntity
us-gaap:LitigationCase
cms:LossContingencyNumberOfLawsuits
us-gaap:StatementEquityComponents
cms:OtherChangesInNoncontrollingInterests

cms:OtherNonoperatingIncomeExpenseRetirementBenefitsNet
dei:LegalEntity

cms:PurchasedPowerRelatedParties
dei:LegalEntity
cms:ReductionOfIncomeTaxExpense
us-gaap:TaxCreditCarryforward
cms:TaxCarryforwardAmountIncreaseDecrease
us-gaap:TaxCreditCarryforward, dei:LegalEntity
dei:LegalEntity
cms:UtilitiesOperatingExpensePurchasedPowerRelatedParties

us-gaap:CapitalExpendituresIncurredButNotYetPaid
dei:LegalEntity

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
dei:LegalEntity

us-gaap:CommonStockDividendsPerShareDeclared
us-gaap:ConcentrationRiskByType, us-gaap:CreditScoreFico, us-gaap:StatementBusinessSegments
us-gaap:ConcentrationRiskPercentage1
us-gaap:ProductOrService, us-gaap:ConcentrationRiskByType, us-gaap:StatementBusinessSegments
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:VariableRate
us-gaap:DebtInstrumentBasisSpreadOnVariableRate1
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:VariableRate
us-gaap:LongtermDebtType, us-gaap:StatementScenario
us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongtermDebtType, us-gaap:StatementScenario
us-gaap:DebtInstrumentInterestRateDuringPeriod
us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DeferredIncomeTaxesAndTaxCredits
dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanContributionsByEmployer
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType, us-gaap:SubsequentEventType
us-gaap:RetirementPlanType, us-gaap:SubsequentEventType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:StatementEquityComponents
us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents, dei:LegalEntity
us-gaap:StatementEquityComponents, dei:LegalEntity
us-gaap:DividendsPreferredStockCash

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate
dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities
dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments
dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes
dei:LegalEntity

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsResearch
dei:LegalEntity

us-gaap:FinanceLeaseInterestExpense
dei:LegalEntity

us-gaap:FinanceLeaseInterestPaymentOnLiability
dei:LegalEntity

us-gaap:FinanceLeasePrincipalPayments
dei:LegalEntity

us-gaap:FinanceLeaseRightOfUseAssetAmortization
dei:LegalEntity

us-gaap:FuelCosts

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables
dei:LegalEntity

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
dei:LegalEntity

us-gaap:IncreaseDecreaseInTimeDeposits

us-gaap:IncrementalCommonSharesAttributableToEquityForwardAgreements

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends

us-gaap:InterestCostsCapitalizedAdjustment
dei:LegalEntity

us-gaap:InterestExpenseOther
dei:LegalEntity

us-gaap:InterestExpenseRelatedParty
dei:LegalEntity

us-gaap:InvestmentIncomeInterestAndDividend
dei:LegalEntity

us-gaap:LeaseCost
dei:LegalEntity

us-gaap:LeaseIncome
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:IncomeTaxAuthorityName
us-gaap:LossContingencyDamagesSoughtValue

us-gaap:OperatingLeaseCost
dei:LegalEntity

us-gaap:OperatingLeasePayments
dei:LegalEntity

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax
dei:LegalEntity
dei:LegalEntity
us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax
us-gaap:StatementEquityComponents, dei:LegalEntity
dei:LegalEntity
us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax

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

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax
dei:LegalEntity
dei:LegalEntity
us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
dei:LegalEntity

us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherNoncashIncomeExpense
dei:LegalEntity

us-gaap:OtherNonoperatingExpense
dei:LegalEntity

us-gaap:OtherNonoperatingIncome
dei:LegalEntity

us-gaap:PaymentsForProceedsFromOtherInvestingActivities
dei:LegalEntity

us-gaap:PaymentsOfOrdinaryDividends
dei:LegalEntity

us-gaap:PaymentsToAcquireLoansReceivable

us-gaap:PaymentsToAcquireNotesReceivable

us-gaap:PensionAndOtherPostretirementBenefitContributions
dei:LegalEntity
dei:LegalEntity
us-gaap:PreferredStockDividendsAndOtherAdjustments
dei:LegalEntity
us-gaap:ProceedsFromContributedCapital

us-gaap:ProceedsFromIssuanceOfCommonStock
us-gaap:SubsidiarySaleOfStock

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities
dei:LegalEntity

us-gaap:ProceedsFromSaleOfProductiveAssets
dei:LegalEntity

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
dei:LegalEntity
dei:LegalEntity, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:StatementScenario
us-gaap:PublicUtilitiesApprovedRateIncreaseDecreaseAmount
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:SubsequentEventType
us-gaap:RepaymentsOfDebt

us-gaap:RepaymentsOfShortTermDebt
dei:LegalEntity
us-gaap:RestructuringCostAndReserve, us-gaap:RestructuringPlan
us-gaap:RestructuringCharges
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodValueNewIssues
us-gaap:StatementEquityComponents
us-gaap:StockRepurchasedDuringPeriodValue

us-gaap:TaxesExcludingIncomeAndExciseTaxes
dei:LegalEntity
us-gaap:UtilitiesOperatingExpense
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseDepreciationAndAmortization
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseFuelUsed
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseGasAndPetroleumPurchased
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseMaintenanceAndOperations
dei:LegalEntity
us-gaap:UtilitiesOperatingExpensePurchasedPower
us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity
dei:LegalEntity
us-gaap:UtilitiesOperatingExpenseTaxes

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

us-gaap:WeightedAverageNumberOfSharesIssuedBasic
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
cms:AccrualForEnvironmentalLossContingenciesInflationRate

cms:AccruedRateRefunds
dei:LegalEntity
us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity

cms:AssetsNoncurrentOtherThanPropertyPlantAndEquipment
dei:LegalEntity
us-gaap:ConsolidatedEntities

cms:DebtInstrumentSupportedByThirdPartyCreditEnhancement
dei:LegalEntity

cms:DeferredPropertyTaxes
dei:LegalEntity

cms:DeferredTaxAssetsNetOperatingLossAndTaxCreditCarryforwards
dei:LegalEntity

cms:DeferredTaxAssetsOperatingLossAndCreditCarryforwards
dei:LegalEntity

cms:DeferredTaxLiabilitiesPostretirementBenefits
dei:LegalEntity
us-gaap:RetirementPlanName
cms:DefinedContributionPlanTrustAssetsAmount
us-gaap:ConsolidatedEntities
cms:FederalIncomeTaxesReceivableCurrent

cms:FinanceLeaseLiabilityAndOtherNoncurrent
dei:LegalEntity
dei:LegalEntity
cms:FinanceLeaseRightOfUseAssetAccumulatedAmortization
dei:LegalEntity
cms:FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:ConsolidatedEntities
cms:InvestmentInSubsidiariesParentOnly

cms:LongTermDebtCurrentMaturitiesLeaseObligationAndOtherFinancingCurrent
dei:LegalEntity

cms:LongTermDebtCurrentMaturitiesLeaseObligationCurrentAndOtherFinancingCurrent
dei:LegalEntity
us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity
cms:NetOverUnderRecoveryOfExpenseIncludingInterestAuthorized
us-gaap:FairValueByFairValueHierarchyLevel
cms:NonqualifiedDeferredCompensationPlanAssetsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity
us-gaap:FairValueByFairValueHierarchyLevel
cms:NonqualifiedDeferredCompensationPlanLiabilitiesFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity
us-gaap:ConsolidatedEntities
cms:NotesPayableIntercompanyPayablesAndRelatedPartyPayables
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, dei:LegalEntity
cms:NotesReceivableRelatedPartiesFairValueDisclosure
us-gaap:FairValueByMeasurementBasis, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
cms:NumberOfFormerManufacturedGasPlants
us-gaap:RetirementPlanType
cms:PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
cms:PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType, dei:LegalEntity

cms:PropertyPlantAndEquipmentGrossExcludingCWIP
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:PublicUtility

cms:PropertyPlantAndEquipmentNetExcludingCWIP
dei:LegalEntity
cms:PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
dei:LegalEntity
cms:PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress
us-gaap:ConsolidationItems, dei:LegalEntity
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments, dei:LegalEntity
dei:LegalEntity
cms:PublicUtilitiesPropertyPlantAndEquipmentNetExcludingCWIP
dei:LegalEntity
cms:PublicUtilitiesPropertyPlantandEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:RetirementPlanType
cms:TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost
us-gaap:RetirementPlanType, dei:LegalEntity

cms:UnionMembershipByTotalEmployeesPercentage
dei:LegalEntity

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

us-gaap:AccountsReceivableGrossCurrent
dei:LegalEntity
us-gaap:FairValueByAssetClass, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingencies
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:Range, us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:AccrualForEnvironmentalLossContingenciesDiscountRate
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesGross
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInFifthYear
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInFourthYear
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInRemainderOfFiscalYear
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInSecondYear
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInThirdYear
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite
us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueWithinOneYear
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

us-gaap:AccumulatedDeferredInvestmentTaxCredit
dei:LegalEntity

us-gaap:AdditionalPaidInCapitalCommonStock
dei:LegalEntity

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
dei:LegalEntity

us-gaap:AllowanceForNotesAndLoansReceivableCurrent

us-gaap:AllowanceForNotesAndLoansReceivableNoncurrent

us-gaap:AssetRetirementObligation
cms:AssetRetirementObligationsCategories
cms:AssetRetirementObligationsCategories, dei:LegalEntity
dei:LegalEntity

us-gaap:AssetRetirementObligationsNoncurrent
dei:LegalEntity
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:AvailableForSaleSecuritiesDebtSecuritiesNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:ConstructionInProgressGross
us-gaap:StatementEquityComponents
us-gaap:CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption

us-gaap:DebtInstrumentCarryingAmount
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:ConsolidatedEntities, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:DebtInstrumentFaceAmount
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:ConsolidatedEntities, us-gaap:LongtermDebtType
us-gaap:CounterpartyName, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType, dei:LegalEntity
us-gaap:CreditFacility, us-gaap:DebtInstrument, dei:LegalEntity
us-gaap:DebtInstrument, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:SubsequentEventType
us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:DebtInstrumentInterestRateEffectivePercentage
us-gaap:CreditFacility, us-gaap:DebtInstrument, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:DeferredFinanceCostsNet
dei:LegalEntity

us-gaap:DeferredIncomeTaxLiabilities
dei:LegalEntity

us-gaap:DeferredIncomeTaxLiabilitiesNet
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:DeferredIncomeTaxesAndOtherAssetsNoncurrent

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsRegulatoryAssetsAndLiabilities
dei:LegalEntity

us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsGeneralBusiness
us-gaap:TaxCreditCarryforward, dei:LegalEntity

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals
dei:LegalEntity

us-gaap:DeferredTaxLiabilitiesDeferredExpenseCapitalizedInventoryCosts
dei:LegalEntity

us-gaap:DeferredTaxLiabilitiesOther
dei:LegalEntity

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment
dei:LegalEntity

us-gaap:DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities
dei:LegalEntity
us-gaap:RetirementPlanName, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanName, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:RetirementPlanType
us-gaap:RetirementPlanName, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligation
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFairValueOfPlanAssets
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanName, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:StatementScenario, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
us-gaap:StatementScenario, us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage
us-gaap:RetirementPlanType, dei:LegalEntity
us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations

us-gaap:DerivativeFairValueOfDerivativeAsset
dei:LegalEntity

us-gaap:DerivativeFairValueOfDerivativeLiability
dei:LegalEntity
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:StatementBusinessSegments
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:DerivativeNotionalAmount
dei:LegalEntity
us-gaap:DueFromRelatedParties

us-gaap:DueFromRelatedPartiesCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:DueFromRelatedPartiesNoncurrent

us-gaap:DueToRelatedPartiesCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:DueToRelatedPartiesCurrentAndNoncurrent
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions
us-gaap:AwardType, dei:LegalEntity

us-gaap:EnergyRelatedInventoryGasStoredUnderground
dei:LegalEntity

us-gaap:EnergyRelatedInventoryOtherFossilFuel
dei:LegalEntity

us-gaap:EquityMethodInvestments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

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

us-gaap:FinanceLeaseLiabilityCurrent
dei:LegalEntity
us-gaap:Range, us-gaap:RelatedPartyTransaction

us-gaap:FinanceLeaseLiabilityNoncurrent
dei:LegalEntity

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

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

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

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

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

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

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

us-gaap:FinanceLeaseRightOfUseAsset
dei:LegalEntity

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent
dei:LegalEntity

us-gaap:FinancingReceivableAllowanceForCreditLosses
cms:CumulativeEffectPeriodOfAdoption
us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, cms:CumulativeEffectPeriodOfAdoption
us-gaap:StatementScenario, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:FinancingReceivableRecordedInvestmentPastDue

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
dei:LegalEntity
us-gaap:IndefiniteLivedIntangibleAssetsByMajorClass
us-gaap:IndefiniteLivedIntangibleAssetsByMajorClass, dei:LegalEntity
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentByType, dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive
dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsGross
dei:LegalEntity
us-gaap:IndefiniteLivedIntangibleAssetsByMajorClass
us-gaap:IndefiniteLivedIntangibleAssetsByMajorClass, dei:LegalEntity
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentByType, dei:LegalEntity
us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsCurrentCarryingValue
us-gaap:LossContingenciesByNatureOfContingency
us-gaap:ConsolidatedEntities
us-gaap:GuaranteeObligationsMaximumExposure
us-gaap:GuaranteeObligationsByNature
us-gaap:LossContingenciesByNatureOfContingency

us-gaap:HeldToMaturitySecurities

us-gaap:HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain

us-gaap:HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss

us-gaap:HeldToMaturitySecuritiesFairValue
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:ConsolidatedEntities
us-gaap:IncomeTaxesReceivable

us-gaap:InterestAndDividendsPayableCurrent
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:InterestBearingDomesticDepositBrokered
us-gaap:JointlyOwnedUtilityPlant, dei:LegalEntity
us-gaap:JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService
us-gaap:JointlyOwnedUtilityPlant, dei:LegalEntity
us-gaap:JointlyOwnedUtilityPlantNetOwnershipAmount
us-gaap:JointlyOwnedUtilityPlant, dei:LegalEntity
us-gaap:JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress
us-gaap:JointlyOwnedUtilityPlant, dei:LegalEntity
us-gaap:JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation
us-gaap:JointlyOwnedUtilityPlant, dei:LegalEntity
us-gaap:JointlyOwnedUtilityPlantProportionateOwnershipShare

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue
dei:LegalEntity

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive
dei:LegalEntity

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
dei:LegalEntity

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive
dei:LegalEntity

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour
dei:LegalEntity

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree
dei:LegalEntity
dei:LegalEntity
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo
dei:LegalEntity
us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
us-gaap:ConsolidatedEntities, us-gaap:LineOfCreditFacility
us-gaap:LettersOfCreditOutstandingAmount
us-gaap:LineOfCreditFacility, dei:LegalEntity
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:LiabilitiesFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:LineOfCreditFacility
us-gaap:LineOfCredit
us-gaap:CreditFacility, dei:LegalEntity
us-gaap:LineOfCreditFacility, dei:LegalEntity
us-gaap:LineOfCreditFacility, dei:LegalEntity
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
us-gaap:ConsolidatedEntities, us-gaap:LineOfCreditFacility
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
us-gaap:LineOfCreditFacility, dei:LegalEntity
us-gaap:LitigationCase
us-gaap:LitigationReserveCurrent
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType, us-gaap:StatementBusinessSegments
us-gaap:LoansAndLeasesReceivableDeferredIncome
us-gaap:StatementBusinessSegments

us-gaap:LoansReceivableHeldForSaleAmount

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

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
dei:LegalEntity

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
dei:LegalEntity

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, dei:LegalEntity
us-gaap:LongtermDebtWeightedAverageInterestRate
us-gaap:LitigationCase, dei:LegalEntity
us-gaap:LossContingencyEstimateOfPossibleLoss
us-gaap:LitigationCase, us-gaap:Range, dei:LegalEntity
us-gaap:Range, us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

us-gaap:NotesAndLoansReceivableNetCurrent
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType, us-gaap:StatementBusinessSegments
us-gaap:ConsolidatedEntities
us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:NotesAndLoansReceivableNetNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:NotesPayableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:NotesReceivableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:NotesReceivableNet
dei:LegalEntity
dei:LegalEntity
us-gaap:NotesReceivableRelatedPartiesCurrent
dei:LegalEntity
us-gaap:NotesReceivableRelatedPartiesNoncurrent
us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:OffBalanceSheetCreditLossLiability

us-gaap:OperatingLeaseLiability
dei:LegalEntity

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityNoncurrent
dei:LegalEntity

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
dei:LegalEntity

us-gaap:OtherInventorySupplies
dei:LegalEntity
us-gaap:RestructuringCostAndReserve, us-gaap:RestructuringPlan
us-gaap:OtherLiabilities

us-gaap:OtherShortTermBorrowings
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities

us-gaap:PreferredStockParOrStatedValuePerShare
dei:LegalEntity
dei:LegalEntity
us-gaap:PreferredStockValue
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:PropertyPlantAndEquipmentOther
dei:LegalEntity
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentDistribution
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment
us-gaap:PublicUtility, dei:LegalEntity
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentTransmission
dei:LegalEntity
us-gaap:RegulatoryAssets
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:RegulatoryAssetsCurrent
dei:LegalEntity
us-gaap:RegulatoryAsset, dei:LegalEntity

us-gaap:RegulatoryAssetsNoncurrent
dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, dei:LegalEntity
us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity
us-gaap:RegulatoryAsset, dei:LegalEntity
dei:LegalEntity
us-gaap:RegulatoryLiabilities

us-gaap:RegulatoryLiabilityCurrent
dei:LegalEntity
us-gaap:RegulatoryLiability, dei:LegalEntity

us-gaap:RegulatoryLiabilityNoncurrent
dei:LegalEntity
us-gaap:RegulatoryLiability, dei:LegalEntity

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

us-gaap:RestrictedCashAndCashEquivalentsNoncurrent
us-gaap:Range
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears
us-gaap:Range
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears
dei:LegalEntity
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedNextTwelveMonths
us-gaap:Range

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter
dei:LegalEntity
us-gaap:Range
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears
us-gaap:Range
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears
dei:LegalEntity
us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
us-gaap:AwardType, dei:LegalEntity
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
us-gaap:AwardType, dei:LegalEntity

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
dei:LegalEntity

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
dei:LegalEntity

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity
us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents, dei:LegalEntity
us-gaap:TaxCreditCarryforward
us-gaap:TaxCreditCarryforwardAmount
us-gaap:TaxCreditCarryforward, dei:LegalEntity

us-gaap:UnbilledReceivablesCurrent
dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased, dei:LegalEntity

us-gaap:UnrecoveredCostsForPurchasedGasAmount
dei:LegalEntity
us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity
us-gaap:ValuationAllowancesAndReservesType
us-gaap:ValuationAllowancesAndReservesBalance
us-gaap:ValuationAllowancesAndReservesType, dei:LegalEntity
us-gaap:VariableInterestEntitiesByClassificationOfEntity
us-gaap:VariableInterestEntityEntityMaximumLossExposureAmount

us-gaap:VariableInterestEntityNonconsolidatedCarryingAmountAssets
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:WeightedAverageRateDomesticDepositBrokered

Tables

  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:CommonStockValue █████████████████████████████████████▁▁▁3333333333333333333333333333333333333222NANANA
us-gaap:CommonStockSharesOutstanding █████████▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▅▅▅▅▅▄▄▄▄▄▄▁▁286283283283283283283283282281281281280279279279279277277276276275275275268266266265265264263263257254252251250249229228NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding 285NA284284283NA283282282NA281280279NA279279277NA276276275NA274274273NA272272270NA269268266NA263261261NA254247NANANA
us-gaap:EarningsPerShareBasic █▆▇▄▇▄▆▅█▁▆▄▇▃▆▅▆▄▅▃▇▄▄▄▇▄▅▃▆▃▆▄▃▂▆▄▅▂▆▄▄▃▄0.860.590.730.330.750.380.60.490.86-0.010.610.330.710.280.670.450.590.390.530.250.730.350.340.310.770.380.480.30.550.260.560.380.260.160.550.40.540.110.580.350.370.290.33
us-gaap:EarningsPerShareDiluted █▆▇▄▇▄▆▅█▁▆▄▇▃▆▅▆▄▅▃▇▄▄▃▇▄▅▃▅▃▆▄▃▂▅▄▅▂▅▄▄▃▄0.850.580.730.330.750.380.590.490.86-0.010.610.330.710.280.670.450.590.380.530.250.730.350.340.30.750.370.460.290.530.250.550.370.250.150.530.380.520.090.530.320.340.280.32
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:Revenues ▄▄▃▂▅▄▃▂▅▄▃▂▄▃▃▂▄▃▂▂▆▄▂▂█▄▂▂▅▃▃▂▄▃▂▂▅▃▂▂▅▁▁1864179515461445205918291599149219531778152714491829164015871371180115091486135021111758143014682523173614451406197916701507133317431620146413642055168214431340196712631225
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 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,cms:ElectricUtility▁▂▆▁▃▂█▃▂▂▆▂102810591250102711031081131310891078108812471077NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▄▄▂▂▅▄▃▂▄▄▃▂▄▃▃▂▄▃▂▂▆▄▂▂█▄▂▂▅▃▃▂▄▃▂▂▅▃▂▂▅▁▁1758179514421347195718291519141318731778152714491829164015871371180115091486135021111758143014682523173614451406197916701507133317431620146413642055168214431340196712631225
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax dei:LegalEntity cms:ConsumersEnergyCompany▆▅▂▁█▅▃▂▇173916351425133119381674149813891849NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,dei:LegalEntity us-gaap:OperatingSegments,cms:CommercialUtilityService,cms:ElectricUtility,cms:ConsumersEnergyCompany▁▃▇▃▂▃█▄339362427362351364434386NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,dei:LegalEntity us-gaap:OperatingSegments,cms:ResidentialUtilityServices,cms:GasUtility,cms:ConsumersEnergyCompany▇▅▁▂█▆▁▂493418111198589435118194NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,cms:ElectricUtility▁▁▆▁▃▂█▃▂102510341247102611001055131010871076NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,cms:GasUtility▇▅▁▂█▆▁▂▇714601178305838619188302773NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments,dei:LegalEntity us-gaap:OperatingSegments,cms:ElectricUtility,cms:ConsumersEnergyCompany▁▁▆▁▃▂█▃10251034124710261100105513101087NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments,dei:LegalEntity us-gaap:OperatingSegments,cms:GasUtility,cms:ConsumersEnergyCompany▇▅▁▂█▆▁▂714601178305838619188302NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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 us-gaap:OperatingIncomeLoss dei:LegalEntity cms:ConsumersEnergyCompany▆▅▆▁▆▃▄▃▆▇▅▃▇▅▇▄▅▃▅▂▇▄▃▃█▄▅▃▆▂▆▄▁▁▅▂▅▂▅▂▃329308319175328231271229334363308222359288365264317246305192379264245227399258314227319207334260183173305207300191304207224NANA
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us-gaap:IncomeTaxExpenseBenefit ▃▆▇▂█▁▅▃▆273742204817332540NA574796NA955874NA7536100NA4743105NA915495NA986738NA811077NA8759614732
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 us-gaap:ProfitLoss dei:LegalEntity cms:ConsumersEnergyCompany█▇▇▂▇▄▆▄█▄▆▂▇▃▆▄▅▄▅▂▇▃▃▃▇▃▄▂▅▁▅▃▁▁▅▂▄▁▅▂▃2352062139822613118015224213618110421111719513217213516084215118119109221119153100162781631227667155921537916088107NANA
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  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
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us-gaap:StockholdersEquity ██▇▇▇▇▇▇▆▆▆▆▆▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▂▁▁▁5185501849574851485847554749467245964441453544494370425342594156410939383902381838023670367036453618345433963323330631943196311130493028304329582887279328212709NANANA
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  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:AssetsCurrent ▆▄▃▃▄▄▄▃▃▄▂▃▃▃▃▂▁▄▂▃▅▅▆▄▇▅▄▄▅▄▄▃▃▅▇▇▆▆█▅2817233123052254237624682374228622072475212122112215228021982031189023202123229125012597273424652969252624012485252824222360220622682565286029562741275930862621NANANA
 us-gaap:AssetsCurrent dei:LegalEntity cms:ConsumersEnergyCompany▅▃▃▂▃▄▂▃▂▄▂▃▂▃▂▁▁▃▃▄▅▅▅▄▅▅▅▅▅▅▅▄▄▆▇██▇22031872186517591794198017451825176619751790191217461942164715641549192918262038220822732256204922362157224421532216225522272110201624072563267926002519NANANANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▇▁▃▃▂▁▃▄▂▂▁▃▄▂▃▃▂▂▁▄▄▂▄▃▆▂▂▄▅▁▁▂▃▂▅█▆▂▆▄▆▂█834140403312234153323477195182142418433235339385177266150477522207493358758172260537586931281873581616239948012476965367551811023
 us-gaap:CashAndCashEquivalentsAtCarryingValue dei:LegalEntity cms:ConsumersEnergyCompany▇▁▃▃▁▁▁▃▂▁▁▄▃▂▁▂▁▁▁▅▅▂▃▂▃▁▃▄▄▁▁▂▃▂▄██▂▃▄▆60411259196373992541154455343182131211172750433974257120098178181992863555571541738537376671371233320591NANA
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 us-gaap:AccountsReceivableNetCurrent dei:LegalEntity cms:ConsumersEnergyCompany▄▅▁▂▆▅▃▃▅▆▁▂▄▅▂▁▃▄▂▂▆▆▂▄█▆▂▃▆▅▂▂▃▅▃▃▆▇7858276116538948556866908588856126487558006165857137586276558888636697391013902669719901844659659737860683706915963NANANANANA
us-gaap:OtherAssetsCurrent ▆▅▅▅▆▆▇▆▆▅███▅▆▇▆▄▅▅▅▄▅▇█▅▄▅▃▂▃▄▂▂▂▁▁▁▁▁101868683971011039310183118117120819410291778789847279108119866879565362705050493739373935NANANA
 us-gaap:OtherAssetsCurrent dei:LegalEntity cms:ConsumersEnergyCompany▆▅▅▅▆▆▆▅▆▅███▄▆▇▆▄▅▆▅▄▅▇█▅▄▅▃▂▃▄▂▂▂▁▁▁857374718683908289711101101147085978466798378637310111177607250455663424343303027NANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ██▇▇▇▇▆▆▆▆▅▅▅▄▄▄▄▄▄▃▃▃▃▃▂▂▃▃▂▂▂▂▂▂▂▂▁▁▁▁7563736072647130723670376909680866826510640363116206605659535922587857475697563355455415532152425168508753555278520051215047497350084901486948024731464646164566NANANA
us-gaap:PropertyPlantAndEquipmentNet ██▇▇▇▇▆▆▅▅▅▄▄▄▃▃▃▃▂▁▁▁19144189261852418106183151812617790172371690416761164441611915857157151544315187149071470514160137751352613412NANANA12246NANANANANANANANANANANANANANANANANA
 us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures dei:LegalEntity cms:ConsumersEnergyCompanyNA1NANANA1NA112121202033343734292826283832343229293030323131293531313134NANANANANA
us-gaap:OtherAssetsNoncurrent ▇▇▅▅▅▄▆███▂▂▃▃▂▂▃▃▂▃▃▃▃▃▃▄▂▂▂▂▁▂▂▂▁▂▂▂▁▁723739492519538478629779789799269294321353258285315384288319354352335362392409233259283293217240268276203234252245178197NANANA
 us-gaap:OtherAssetsNoncurrent dei:LegalEntity cms:ConsumersEnergyCompany▇▇▅▅▅▅▆███▁▂▂▃▁▂▂▃▂▂▂▂▂▂▃▃▁▂▂▂▁▁▂▂▁▁▂▂619637407434458410545660674687160189218250151179209262165194230236208233263283149172198209134157179196123150174176NANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:LiabilitiesCurrent ▆▅▃▄▃▅█▅▅▆▄▃▃▅▃▃▃▄▂▂▁▃▂▁▂▃▁▂▂▂▁▂▂▄▄▄▄▃▄▂2940270421652386210626243442253524822784226121151926265520692091204723021788164015992014164815631801194514641802164517971485180718192338221422412290202122971736NANANA
 us-gaap:LiabilitiesCurrent dei:LegalEntity cms:ConsumersEnergyCompany▄▅▁▂▂▄█▄▇▇▄▄▃▇▂▄▃▅▂▁▁▃▁▂▃▃▁▂▂▃▁▂▁▄▃▃▂▁16711712115612571298161823071635205621361679158314002094130315711511173113151146108013861161128813431480111711881286141011301274109016421383136312871161NANANANANA
 us-gaap:DebtCurrent us-gaap:ConsolidatedEntities srt:ParentCompanyNA0NANANA180NANANA225NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NotesPayableCurrent ▁▃▁▁▂▃█▁0900030972790NA170230NANA39875NANA24968NANA60NANANA170NANANA110NANANANANANANANANANANANANA
 us-gaap:NotesPayableCurrent dei:LegalEntity cms:ConsumersEnergyCompany▁▃▁▁▂▃█▁0900030972790NA170230NANA39875NANA24968NANA60NANANA170NANANA110NANANANANANANANANANANANANA
us-gaap:LongTermDebtCurrent ▇▄▄▄▃▄█▅▅▄▄▃▃▃▄▃▃▂▂▁▁▁▂▁▂▂▁▃▂▁▁▂▃▄▄▄17001111110011008219741900120013001081959819790864984897929684720498521519669418645541511737711519488631814103311161099NA726NANANANANA
 us-gaap:LongTermDebtCurrent dei:LegalEntity cms:ConsumersEnergyCompany▅▂▂▁▁▁█▄▆▄▄▄▃▄▃▄▄▂▃▂▂▂▁▁▁▁▁▁▃▁▁▁▁▄▄▄50220210226262687637669334344337330537527544844819826110011312460454443424224141404039339338338NA37NANANANANA
us-gaap:AccountsPayableCurrent ▃▆▅▆▄█▇▆▄█▆▅▃▅▄▄▄▆▅▄▃▇▅▅▆▅▃▃▁▃▃▄▁▅▃▂▁▃▂▂490622598627544723680623534725624599479598539559534633586558512678604587632585519512426512491527409575484444413492456451NANANA
 us-gaap:AccountsPayableCurrent dei:LegalEntity cms:ConsumersEnergyCompany▂▆▅▆▄█▇▆▄█▆▅▃▅▄▄▄▆▅▄▃▇▅▅▆▅▄▃▁▃▃▄▁▅▃▂▁▃458593569595515685636594514701601580465580521545521613571540496662591573611571508502414501480512396561473429403471NANANANANA
us-gaap:TaxesPayableCurrent ▆█▂▅▅▇▁▅▅▆▁▄▄▆▁▄▄▆▁▄▄▆▁▄▄▅▁▃▄▅▁▃▃▅▁▄▄▅▂▄330437125295295398107267265360902562603489325225434990235239316892252252978820621127983199206282103239239302114230NANANA
 us-gaap:TaxesPayableCurrent dei:LegalEntity cms:ConsumersEnergyCompany▅▇▂▄▅▆▂▄▇█▁▄▄▅▂▄▄▅▁▂▂▂▂▄▅▅▃▅▅▅▃▄▄▄▁▂▃▃36348115829836943614827948454211125729135411426526235278166140149159283343353201316329376198271250287102163182199NANANANANA
us-gaap:OtherLiabilitiesCurrent ▅▇▆▇▄▄▃▂▃█▃▄▃█▅▂▂▄▃▂▂▅▂▃▃▄▃▃▃▄▃▃▃▅▃▂▁▄▂▂162186170182148147134117134195130145135199159127118142130123117163124129131146136139134152137136139159131122109144119117NANANA
 us-gaap:OtherLiabilitiesCurrent dei:LegalEntity cms:ConsumersEnergyCompany▃▄▅▆▄▄▃▂▃█▂▄▃█▅▂▂▄▃▂▂▆▃▃▃▄▃▃▃▄▃▄▃▄▂▂▁▃10511812714211512096841031599310899164127938710910093901359997101112991009710910510810311994857695NANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:LiabilitiesNoncurrent ███▇▇▆▅▅▅▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▂▂▃▃▂▂▂▂▂▁▁▁▁▁▁19285190781885018018177921711315685160681575315788152871526615290146771447714179138441406313725137431376013464130261247412468119801208912267122741209611883113311124811042106571070210421107581040810322NANANA
 us-gaap:LiabilitiesNoncurrent dei:LegalEntity cms:ConsumersEnergyCompany██▇▇▇▇▅▆▅▅▅▅▅▅▄▄▄▄▄▄▄▄▃▂▂▂▂▃▂▂▂▂▂▁▁▁▁▁144321425014046135121343013487122621276012180124751216912160121781191311716112151119511381111401125511258111841050798499874984210140104301018310283100719696967496269264938593169498NANANANANA
us-gaap:LongTermDebtNoncurrent █▇▇▇▆▆▄▅▄▄▄▄▄▄▄▄▃▄▃▃▃▃▃▃▃▂▂▂▂▂▂▁▁▁▁▁▁▂▁▁1254511951120401123611105106158869927289969123902490919129864087228486817084417903804081438016804275357536710170896695674167106711622161936040603761845926644860135883NANANA
 us-gaap:LongTermDebtNoncurrent dei:LegalEntity cms:ConsumersEnergyCompany█▇▇▆▆▆▃▄▃▄▄▄▄▃▄▃▃▃▃▃▃▃▃▂▂▂▂▂▁▂▂▁▁▁▁▁▁▂76167048708765466565677952395738521155615275533954195253536549224934520649695141515451545230455545674579459142764086429743083967397739873997416941794488NANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ▁▄▃▃▃▃▅▄▄▄▄▄▄▄▃▃▃▃▅▅▅▅▂▂▂▂▄███▇▇▇▇▆▆▆▆▇▇1416744474434404367977877787667607707817895605705815918478468448722422412402397401393139814511291128912881289113911361135113512831276NANANA
 us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent dei:LegalEntity cms:ConsumersEnergyCompany▁▄▃▃▃▃▄▄▄▄▄▄▄▄▃▃▃▃▅▅▅▅▁▁▁▁▄███▇▇▇▇▆▆▆▆10362240440039639274173172171170371272373050051051952977076876679318318218017970213291334138512291227122512251081107810761076NANANANANA
us-gaap:MinorityInterest ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▇▇▇▇▇▇▇▇▇▇██37373737373737373737373737373737373737373737373737373737444444444444444444444545NANANA
us-gaap:OtherLiabilitiesNoncurrent █▇▇▆▅▃▃▃▃▃▃▂▃▂▂▃▄▄▃▃▃▃▃▃▃▃▄▄▃▃▄▅▄▅▁▂▂▁▂▃395383373364345294295305307307308289295290283301314313299304304299307303307306316316311311323336328336265278288267278296NANANA
 us-gaap:OtherLiabilitiesNoncurrent dei:LegalEntity cms:ConsumersEnergyCompany██▇▇▆▄▄▄▅▄▄▃▃▃▃▄▄▄▄▄▄▄▄▅▅▅▅▅▅▅▅▅▅▅▁▂▂▁311304298291274230233243244241241219223218212231243236239243241237243251253252260259253252252262254256178186187176NANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:StockholdersEquity ██▇▇▇▇▇▇▆▆▆▆▆▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▂▁▁▁5185501849574851485847554749467245964441453544494370425342594156410939383902381838023670367036453618345433963323330631943196311130493028304329582887279328212709NANANA
 us-gaap:StockholdersEquity dei:LegalEntity cms:ConsumersEnergyCompany█▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▂▂▂▁▁▁▁▁80667700769976107287688368866851667664516495642562095902592458795679550954855429547952405214521350584820480047544759453845594540445943504367430943104136NANANANANA
us-gaap:CommonStockValue █████████████████████████████████████▁▁▁3333333333333333333333333333333333333222NANANA
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 us-gaap:RetainedEarningsAccumulatedDeficit dei:LegalEntity cms:ConsumersEnergyCompany███▇▇▇▇▇▇▆▆▅▅▅▅▅▄▄▄▄▄▃▃▃▃▃▃▂▂▂▂▂▁▂▂▁▁▁1529151315041415141813641373134013151173121311431128106510871040967950931876925832797798810724711665667598611593515554569511512463NANANANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▁▁▂▂▂▂▃▃▃▄▅▄▄▄▅▅▅▅▄▄▄▄████▆▄▄▄▅▅▅▄▆▆▆▆▇▇-76-73-67-67-66-65-59-61-61-50-47-48-49-50-45-47-47-47-49-48-48-49-20-20-21-22-39-56-54-55-43-45-47-49-40-38-40-40-31-31NANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
us-gaap:NetCashProvidedByUsedInOperatingActivities ▂▅▂▇█▁▁201395210568617138149NA708NA80NA646NANANANANANANANANANANA611NANANA725NANANA635NANANA841NANANA657NANA
 us-gaap:NetCashProvidedByUsedInOperatingActivities dei:LegalEntity cms:ConsumersEnergyCompany▂▄▁▆█▂▁238350141491619194157NA720NA84NA648NANANANANANANANANANANA646NANANA713NANANA681NANANA867NANANA683NANA
us-gaap:NetCashProvidedByUsedInInvestingActivities █▇▁▃▅▁▁-559-604-802-735-675-791-807NA-456NA-548NA-346NANANANANANANANANANANA-346NANANA-293NANANA-313NANANA-228NANANA-212NANA
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 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType,dei:LegalEntity cms:ThreePointThreeSevenFivePercentFirstMortgageBondsDue2023,cms:FirstMortgageBonds,cms:ConsumersEnergyCompanyNA0.03375NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType,dei:LegalEntity cms:ThreePointTwoFiveZeroPercentFirstMortgageBondsDue2046,cms:FirstMortgageBonds,cms:ConsumersEnergyCompanyNA0.0325NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType,dei:LegalEntity cms:TwoPointEightFiveZeroPercentFirstMortgageBondsDue2022,cms:FirstMortgageBonds,cms:ConsumersEnergyCompanyNA0.0285NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:SubsequentEventType,dei:LegalEntity cms:FirstMortgageBondsDueOctober2020,us-gaap:SubsequentEvent,cms:ConsumersEnergyCompanyNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value33333333333333333333333333333333333332222
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Shares Issued

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value286283283283283283283283282281281281280279279279279277277276276275275275268266266265265264263263257254252251250249229228227
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:CommonStock



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value283283281279277275266264254
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-30
Value285284284283283282282281280279279279277276276275274274273272272270269268266263261261254247
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value0.860.590.730.330.750.380.60.490.86-0.010.610.330.710.280.670.450.590.390.530.250.730.350.340.310.770.380.480.30.550.260.560.380.260.160.550.40.540.110.580.350.370.290.33
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value0.850.580.730.330.750.380.590.490.86-0.010.610.330.710.280.670.450.590.380.530.250.730.350.340.30.750.370.460.290.530.250.550.370.250.150.530.380.520.090.530.320.340.280.32
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

Income Loss From Continuing Operations Per Diluted Share

Revenues

us-gaap:Revenues



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value1864179515461445205918291599149219531778152714491829164015871371180115091486135021111758143014682523173614451406197916701507133317431620146413642055168214431340196712631225
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value17441670142913341943171215021395185516861437136217371550149812931723143914171281202816721359138723821674138613421919160814481282167515651397130319881620137012761890
Percentage of Revenues93.693.092.492.394.493.693.993.595.094.894.194.095.094.594.494.395.795.495.494.996.195.195.094.594.496.495.995.497.096.396.196.296.196.695.495.596.796.394.995.296.1
Percentage of Revenues93.693.092.492.394.493.693.993.595.094.894.194.095.094.594.494.395.795.495.494.996.195.195.094.594.496.495.995.497.096.396.196.296.196.695.495.596.796.394.995.296.1
Percentage of Revenues cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value102810591250102711031081131310891078108812471077
Percentage of Revenues55.259.080.971.153.659.182.173.055.261.281.774.3
Percentage of Revenues55.259.080.971.153.659.182.173.055.261.281.774.3
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-03-31
Value6249
Percentage of Revenues3.32.4
Percentage of Revenues3.32.4
Percentage of Revenues us-gaap:OperatingSegments cms:EnerBank100.0100.0

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value586459586771576163575855
Percentage of Revenues3.13.63.84.03.33.93.64.13.23.23.83.8
Percentage of Revenues3.13.63.84.03.33.93.64.13.23.23.83.8
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value716611179307840631189306777598190285
Percentage of Revenues38.434.011.621.240.834.511.820.539.833.612.419.7
Percentage of Revenues38.434.011.621.240.834.511.820.539.833.612.419.7
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value10281059125010271103108113131089
Percentage of Revenues55.259.080.971.153.659.182.173.0
Percentage of Revenues55.259.080.971.153.659.182.173.0
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value716611179307840631189306
Percentage of Revenues38.434.011.621.240.834.511.820.5
Percentage of Revenues38.434.011.621.240.834.511.820.5
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0100.0100.0

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value1758179514421347195718291519141318731778152714491829164015871371180115091486135021111758143014682523173614451406197916701507133317431620146413642055168214431340196712631225
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues94.3100.093.393.295.0100.095.094.795.9100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value173916351425133119381674149813891849
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax98.991.198.898.899.091.598.698.398.7
Percentage of Revenues93.391.192.292.194.191.593.793.194.7
Percentage of Revenues cms:ConsumersEnergyCompany99.797.999.799.899.797.899.799.699.7

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

us-gaap:OperatingSegments, cms:OtherUtilityService, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value192217161923212424
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.11.21.21.21.01.31.41.71.3
Percentage of Revenues1.01.21.11.10.91.31.31.61.2
Percentage of Revenues us-gaap:OperatingSegments cms:OtherUtilityService cms:Enterprises0.00.00.00.00.00.00.00.00.0

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

us-gaap:OperatingSegments, cms:CommercialUtilityService, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value339362427362351364434386
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.320.229.626.917.919.928.627.3
Percentage of Revenues18.220.227.625.117.019.927.125.9
Percentage of Revenues us-gaap:OperatingSegments cms:CommercialUtilityService cms:ElectricUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:CommercialUtilityService, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value14911327581741173058
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.56.31.94.38.96.42.04.1
Percentage of Revenues8.06.31.74.08.56.41.93.9
Percentage of Revenues us-gaap:OperatingSegments cms:CommercialUtilityService cms:GasUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:IndustrialUtilityService, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value140158175174162175186170
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.08.812.112.98.39.612.212.0
Percentage of Revenues7.58.811.312.07.99.611.611.4
Percentage of Revenues us-gaap:OperatingSegments cms:IndustrialUtilityService cms:ElectricUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:IndustrialUtilityService, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value201538251849
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.10.80.20.61.31.00.30.6
Percentage of Revenues1.10.80.20.61.21.00.30.6
Percentage of Revenues us-gaap:OperatingSegments cms:IndustrialUtilityService cms:GasUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:OtherUtilityService, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value6557606764686556
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.73.24.25.03.33.74.34.0
Percentage of Revenues3.53.23.94.63.13.74.13.8
Percentage of Revenues us-gaap:OperatingSegments cms:OtherUtilityService cms:ElectricUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:OtherUtilityService, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value5255374150493641
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.03.12.63.02.62.72.42.9
Percentage of Revenues2.83.12.42.82.42.72.32.7
Percentage of Revenues us-gaap:OperatingSegments cms:OtherUtilityService cms:GasUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:ResidentialUtilityServices, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value481457585423523448625475
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax27.425.540.631.426.724.541.133.6
Percentage of Revenues25.825.537.829.325.424.539.131.8
Percentage of Revenues us-gaap:OperatingSegments cms:ResidentialUtilityServices cms:ElectricUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, cms:ResidentialUtilityServices, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value493418111198589435118194
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax28.023.37.714.730.123.87.813.7
Percentage of Revenues26.423.37.213.728.623.87.413.0
Percentage of Revenues us-gaap:OperatingSegments cms:ResidentialUtilityServices cms:GasUtility cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value102510341247102611001055131010871076
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax58.357.686.576.256.257.786.276.957.4
Percentage of Revenues55.057.680.771.053.457.781.972.955.1
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility99.797.699.899.999.797.699.899.899.8

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value192217161923212424
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.11.21.21.21.01.31.41.71.3
Percentage of Revenues1.01.21.11.10.91.31.31.61.2
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises32.834.428.827.628.432.436.839.338.1

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value714601178305838619188302773
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax40.633.512.322.642.833.812.421.441.3
Percentage of Revenues38.333.511.521.140.733.811.820.239.6
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility99.798.499.499.399.898.199.598.799.5

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value10251034124710261100105513101087
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax58.357.686.576.256.257.786.276.9
Percentage of Revenues55.057.680.771.053.457.781.972.9
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany99.797.699.899.999.797.699.899.8

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value714601178305838619188302
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax40.633.512.322.642.833.812.421.4
Percentage of Revenues38.333.511.521.140.733.811.820.2
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany99.798.499.499.399.898.199.598.7

us-gaap:ProductOrService

cms:OtherUtilityService



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value192217161923212424
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.11.21.21.21.01.31.41.71.3
Percentage of Revenues1.01.21.11.10.91.31.31.61.2
Percentage of Revenues cms:OtherUtilityService0.00.00.00.00.00.00.00.00.0

us-gaap:ProductOrService, dei:LegalEntity

cms:CommercialUtilityService, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value488475454420525481464444
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax27.826.531.531.226.826.330.531.4
Percentage of Revenues26.226.529.429.125.526.329.029.8
Percentage of Revenues cms:CommercialUtilityService cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

cms:IndustrialUtilityService, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value160173178182187193190179
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.19.612.313.59.610.612.512.7
Percentage of Revenues8.69.611.512.69.110.611.912.0
Percentage of Revenues cms:IndustrialUtilityService cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

cms:OtherUtilityService, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1171129710811411710197
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax6.76.26.78.05.86.46.66.9
Percentage of Revenues6.36.26.37.55.56.46.36.5
Percentage of Revenues cms:OtherUtilityService cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

cms:ResidentialUtilityServices, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value9748756966211112883743669
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax55.448.748.346.156.848.348.947.3
Percentage of Revenues52.348.745.043.054.048.346.544.8
Percentage of Revenues cms:ResidentialUtilityServices cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

Cost Of Goods And Services Sold

us-gaap:ProductOrService

us-gaap:CostOfGoodsAndServicesSold

us-gaap:ElectricityPurchased



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value357349413356378391447393382371426
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues19.219.426.724.618.421.428.026.319.620.927.9
Percentage of Revenues us-gaap:ElectricityPurchased0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OilAndGasPurchased



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value273224351064042954811238125647
Percentage of CostOfGoodsAndServicesSold76.564.28.529.8106.975.410.728.599.769.011.0
Percentage of Revenues14.612.52.37.319.616.13.07.519.514.43.1
Percentage of Revenues us-gaap:OilAndGasPurchased0.00.00.00.00.00.00.00.00.00.00.0

Operating Expenses

Costs And Expenses

us-gaap:CostsAndExpenses



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-31
Value149614841195122717001579130512371590119712081441120110861465116911461714
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues80.382.777.384.982.686.381.682.981.478.483.478.875.779.281.378.784.981.2

Operating Income Loss

us-gaap:OperatingIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value368311351218359250294255363379330241388290386285336245317204397273236235408264317232329212343260188174316207306158319262239230150
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues19.717.322.715.117.413.718.417.118.621.321.616.621.217.724.320.818.716.221.315.118.815.516.516.016.215.221.916.516.612.722.819.510.810.721.615.214.99.422.119.612.218.212.2

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value329308319175328231271229334363308222359288365264317246305192379264245227399258314227319207334260183173305207300191304207224
Percentage of OperatingIncomeLoss89.499.090.980.391.492.492.289.892.095.893.392.192.599.394.692.694.3100.496.294.195.596.7103.896.697.897.799.197.897.097.697.4100.097.399.496.5100.098.0120.995.379.093.7
Percentage of Revenues17.717.220.612.115.912.616.915.317.120.420.215.319.617.623.019.317.616.320.514.218.015.017.115.515.814.921.716.116.112.422.219.510.510.720.815.214.611.421.115.411.4
Percentage of Revenues cms:ConsumersEnergyCompany18.918.422.313.116.913.518.016.418.021.521.416.320.718.624.420.418.417.121.515.018.715.818.016.416.815.422.716.916.612.923.120.310.911.121.815.915.111.822.216.211.9

Interest Expense

us-gaap:InterestExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value1371341331311211211141121111111101071101081061011031011011011019910298969899104104105102117105103105
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues7.37.58.69.15.96.67.17.55.77.37.65.96.97.95.96.87.64.87.16.94.06.97.35.06.47.45.77.17.65.17.18.75.38.28.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value797775747174737072706968676667656665646061606261596164666766647868
Percentage of InterestExpense57.757.556.456.558.761.264.062.564.963.162.763.660.961.163.264.464.164.463.459.460.460.660.862.261.562.264.663.564.462.962.766.764.8
Percentage of Revenues4.24.34.95.13.44.04.64.73.74.64.83.74.24.83.74.44.93.14.54.12.44.24.43.13.94.63.74.54.93.24.45.83.5
Percentage of Revenues cms:ConsumersEnergyCompany4.54.65.25.53.74.34.95.03.94.95.13.94.55.13.94.65.23.24.74.32.64.34.63.24.14.83.84.75.13.34.76.13.6

Interest Expense Debt

us-gaap:InterestExpenseDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value11611211111010610810110310010110310010310310095979698999796999492949499991009798989798
Percentage of InterestExpenseDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues6.26.27.27.65.15.96.36.95.16.67.15.56.57.55.66.47.24.56.96.73.86.67.04.76.17.15.46.87.34.96.77.35.07.78.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value747169686973696767666666656565626363625959586059565861626363606063
Percentage of InterestExpenseDebt63.863.462.261.865.167.668.365.067.065.364.166.063.163.165.065.364.965.663.359.660.860.460.662.860.961.764.962.663.663.061.961.264.3
Percentage of Revenues4.04.04.54.73.44.04.34.53.44.34.63.64.14.73.64.24.73.04.34.02.34.04.33.03.74.43.54.24.63.14.24.53.2
Percentage of Revenues cms:ConsumersEnergyCompany4.24.34.85.13.64.34.64.83.64.64.83.84.35.03.84.44.93.14.64.32.54.24.53.13.94.53.64.44.83.24.44.73.3

Other Nonoperating Income Expense

Income Loss From Continuing Operations

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

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-30
Value270205249114261126202165281229140295281183238223104302141127309218
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues14.511.416.17.912.76.912.611.114.415.09.716.117.713.313.215.07.714.39.98.712.215.1

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-30
Value279254270124280162220179286243157312298201254243128325184169337255
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest103.3123.9108.4108.8107.3128.6108.9108.5101.8106.1112.1105.8106.0109.8106.7109.0123.1107.6130.5133.1109.1117.0
Percentage of Revenues15.014.217.58.613.68.913.812.014.615.910.817.118.814.714.116.49.515.412.911.513.417.6
Percentage of Revenues cms:ConsumersEnergyCompany16.015.218.99.314.49.514.612.815.416.911.518.019.915.514.717.110.016.013.512.214.118.4

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

Income Loss From Continuing Operations Before Income Taxes Domestic

Income Loss From Continuing Operations Attributable To Noncontrolling Entity

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-06-302013-03-312012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value3928312723-3222229109145687366-725869989161416-442
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.11.62.01.91.1-0.21.41.51.50.70.60.80.30.40.40.50.20.30.4-0.50.10.40.40.50.50.60.60.41.11.00.8-0.33.4

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value292326232352220245421934321132-1127-539469121213
Percentage of NonoperatingIncomeExpense74.482.183.985.2100.0-166.7100.090.982.850.044.4150.0180.050.050.042.966.7183.350.0-28.6-50.00.040.087.50.050.0100.044.475.0100.075.085.781.2
Percentage of Revenues1.61.31.71.61.10.31.41.31.20.30.31.10.60.20.20.20.10.50.20.1-0.00.10.10.4-0.30.20.50.30.40.40.80.90.7
Percentage of Revenues cms:ConsumersEnergyCompany1.71.41.81.71.20.31.51.41.30.30.31.20.60.20.20.20.20.50.20.1-0.00.10.10.4-0.30.20.50.30.50.50.90.90.7

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value273742204817332540574796955874753610047431059154959867388110778759614732
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues1.42.12.71.42.30.92.11.72.03.73.25.26.04.24.15.02.74.73.32.94.26.33.84.86.55.02.25.50.73.76.04.43.13.72.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value4448572654314027446253101103698283441106560116102671031078052885490925362
Percentage of IncomeTaxExpenseBenefit163.0129.7135.7130.0112.5182.4121.2108.0110.0108.8112.8105.2108.4119.0110.8110.7122.2110.0138.3139.5110.5112.1124.1108.4109.2119.4136.8108.6540.0116.9105.789.8101.6
Percentage of Revenues2.42.73.71.82.61.72.51.82.34.13.75.56.55.04.65.63.35.24.54.14.67.14.85.27.16.03.06.04.04.46.44.03.2
Percentage of Revenues cms:ConsumersEnergyCompany2.52.94.01.92.81.82.71.92.44.33.95.86.95.34.85.93.45.44.84.34.97.45.05.47.46.23.16.34.14.56.74.23.3

Income Taxes Paid Net

Profit Loss

us-gaap:ProfitLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value24316820794213109169140241-2172931997818612516410714868202979484204102127811446714910167411401011352514684887580
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues13.09.413.46.510.36.010.69.412.3-0.111.36.410.94.811.79.19.17.110.05.09.65.56.65.78.15.98.85.87.34.09.97.63.82.59.67.46.61.510.16.34.55.96.5

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value2352062139822613118015224213618110421111719513217213516084215118119109221119153100162781631227667155921537916088107
Percentage of ProfitLoss96.7122.6102.9104.3106.1120.2106.5108.6100.4-6800.0105.2111.8106.0150.0104.8105.6104.9126.2108.1123.5106.4121.6126.6129.8108.3116.7120.5123.5112.5116.4109.4120.8113.4163.4110.791.1113.3316.0109.6104.8121.6
Percentage of Revenues12.611.513.86.811.07.211.310.212.47.611.97.211.57.112.39.69.68.910.86.210.26.78.37.48.86.910.67.18.24.710.89.24.44.110.66.77.44.711.16.65.4
Percentage of Revenues cms:ConsumersEnergyCompany13.512.314.97.311.67.712.010.913.08.112.67.612.17.513.010.210.09.411.36.610.67.18.87.99.37.111.07.58.44.911.39.54.54.311.17.17.74.911.76.95.7

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2020-03-312019-03-312018-03-31
Value-26-14-16
Percentage of ProfitLoss-10.7-6.6-6.6
Percentage of Revenues-1.4-0.7-0.8
Percentage of Revenues cms:CorporateAndReconcilingItems0.0-28.6-45.7

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-03-312018-03-31
Value118105139
Percentage of ProfitLoss48.649.357.7
Percentage of Revenues6.35.17.1
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility11.59.512.9

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-03-31
Value1411
Percentage of ProfitLoss5.85.2
Percentage of Revenues0.80.5
Percentage of Revenues us-gaap:OperatingSegments cms:EnerBank22.622.4

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-03-312018-03-31
Value20115
Percentage of ProfitLoss8.20.56.2
Percentage of Revenues1.10.00.8
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises34.51.523.8

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-03-312018-03-31
Value117121103
Percentage of ProfitLoss48.156.842.7
Percentage of Revenues6.35.95.3
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility16.314.413.3

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-03-31
Value118105
Percentage of ProfitLoss48.649.3
Percentage of Revenues6.35.1
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany11.59.5

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-03-31
Value117121
Percentage of ProfitLoss48.156.8
Percentage of Revenues6.35.9
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany16.314.4

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-03-312012-06-302012-03-312011-06-302011-03-312010-06-302010-03-31
Value2432079321316913924117292199186124164148672029483204144100671001358288
Percentage of ProfitLoss100.0100.098.9100.0100.099.3100.0100.098.9100.0100.099.2100.0100.098.5100.0100.098.8100.0100.099.0100.099.0100.097.6100.0
Percentage of Revenues13.013.46.410.310.69.312.311.36.310.911.79.09.110.05.09.66.65.78.17.37.53.87.36.66.14.5
Percentage of Revenues us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:RetainedEarnings, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value23520621398226131180152
Percentage of ProfitLoss96.7122.6102.9104.3106.1120.2106.5108.6
Percentage of Revenues12.611.513.86.811.07.211.310.2
Percentage of Revenues us-gaap:RetainedEarnings cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-09-302017-06-302016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value161207921041711391739318812416414767203948420515010269137102135
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues9.013.46.45.710.79.311.36.411.89.09.19.95.09.66.65.78.110.07.74.09.47.56.6

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-09-302017-06-302016-06-302015-06-302014-06-302013-09-302013-06-302012-09-302012-06-30
Value1000000.00.01000000.01000000.00.01000000.00.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.0
Percentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest100.00.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.10.00.10.10.00.10.00.10.10.10.10.10.10.10.1

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value24016220793212105171140241173942001881251641476894852051447914515110369
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues12.99.013.46.410.35.710.79.412.311.36.510.911.89.19.19.95.06.65.88.110.05.67.310.07.74.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-03-31
Value23519821399226137182152242132181105205175
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest97.9122.2102.9106.5106.6130.5106.4108.6100.40.0104.6111.7102.5106.7
Percentage of Revenues12.611.013.86.911.07.511.410.212.47.411.97.211.29.7
Percentage of Revenues cms:ConsumersEnergyCompany13.511.914.97.411.68.012.110.913.07.812.67.711.810.2

Net Income Loss

us-gaap:NetIncomeLoss



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value16720793213108169139241-3172921997718612416410614867202969483204102126801446714810067411391001352514582886978
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues9.313.46.410.35.910.69.312.3-0.211.36.310.94.711.79.09.17.010.05.09.65.56.65.78.15.98.75.77.34.09.87.53.82.59.57.36.61.510.06.14.55.56.4

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value-102-13-15-24-15-26-82-17-18
Percentage of NetIncomeLoss-61.1-6.3-16.1-22.2-8.9-18.72733.3-9.9-19.6
Percentage of Revenues-5.7-0.8-1.0-1.3-0.9-1.7-4.6-1.1-1.2
Percentage of Revenues cms:CorporateAndReconcilingItems0.0-22.4-28.3-52.2-37.5-72.2-234.3-53.1-56.2

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value9122390671991306117694
Percentage of NetIncomeLoss54.5107.796.862.0117.893.5-2033.3102.3102.2
Percentage of Revenues5.114.46.23.712.48.73.411.56.5
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility8.617.88.86.215.211.95.614.18.7

us-gaap:OperatingSegments, cms:Enterprises



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value157101414-5487
Percentage of NetIncomeLoss9.03.410.80.92.410.11800.04.77.6
Percentage of Revenues0.80.50.70.10.30.9-3.00.50.5
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises23.411.917.21.47.023.0-94.713.812.7

us-gaap:OperatingSegments, cms:GasUtility



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value114-10864-19217259
Percentage of NetIncomeLoss68.3-4.88.659.3-11.215.1-2400.02.99.8
Percentage of Revenues6.4-0.60.63.5-1.21.44.00.30.6
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility18.7-5.62.610.1-10.16.912.02.63.2

Net Income Loss Available To Common Stockholders Basic

dei:LegalEntity

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value205213972261301801512421351811032111161951311721341608321511711910822111915299162781621217667154911537915987107
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues11.413.86.711.07.111.310.112.47.611.97.111.57.112.39.69.68.910.86.110.26.78.37.48.86.910.57.08.24.710.79.14.44.110.56.77.44.711.06.55.4
Percentage of Revenues cms:ConsumersEnergyCompany12.314.97.311.67.612.010.813.08.012.67.612.17.513.010.110.09.311.36.510.67.08.87.89.37.111.07.48.44.911.29.44.54.311.07.07.74.911.66.85.7

us-gaap:ConsolidationItems, dei:LegalEntity

cms:CorporateAndReconcilingItems, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value0.00.0-1000000.0-1000000.00.00.0
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic0.00.0-1.0-0.80.00.0
Percentage of Revenues0.00.0-0.1-0.10.00.0
Percentage of Revenues cms:CorporateAndReconcilingItems cms:ConsumersEnergyCompany0.00.00.00.00.00.0

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value912239067199130
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic44.4104.792.851.5110.686.1
Percentage of Revenues5.114.46.23.712.48.7
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany8.617.88.86.215.211.9

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value114-10864-1921
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic55.6-4.78.249.2-10.613.9
Percentage of Revenues6.4-0.60.63.5-1.21.4
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany18.7-5.62.610.1-10.16.9

Net Income Loss Attributable To Noncontrolling Interest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-06-302015-12-312015-06-302014-12-312014-06-302013-09-302013-06-302012-09-302012-06-302011-09-302011-06-302010-09-302010-06-302009-09-302009-06-30
Value1010101010101111111111111262
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.00.0100.00.0100.00.0100.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.10.00.10.00.10.00.10.00.10.00.10.00.10.10.10.10.10.10.10.10.10.10.10.10.10.10.50.2

Assets

us-gaap:Assets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value2744726837260092529224793245292391323312228682305022120218672162321622208422046320037203401945219238191981918518381177191792417416169861742917269171311660816293161601645215958159451564215616155711505115256
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value242062369922938224162205222025214922128320949210992038020205198241994618980187021842218658179771786717854178471691916387163121617916094164091627216275158041555415267156621505815101149571483914622
Percentage of Assets88.288.388.288.688.989.889.991.391.691.592.192.491.792.291.191.491.991.792.492.993.093.092.092.591.092.994.794.194.295.095.295.594.595.294.494.795.695.095.8
Percentage of Assets88.288.388.288.688.989.889.991.391.691.592.192.491.792.291.191.491.991.792.492.993.093.092.092.591.092.994.794.194.295.095.295.594.595.294.494.795.695.095.8
Percentage of Assets cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value870279797645
Percentage of Assets32.432.533.2
Percentage of Assets32.432.533.2
Percentage of Assets srt:ParentCompany100.0100.0100.0

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value1794827022484235121042012172916631478
Percentage of Assets0.70.210.49.89.58.68.47.47.26.8
Percentage of Assets0.70.210.49.89.58.68.47.47.26.8
Percentage of Assets cms:CorporateAndReconcilingItems100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, dei:LegalEntity

cms:CorporateAndReconcilingItems, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-312017-12-31
Value222022202953
Percentage of Assets0.10.10.10.10.10.2
Percentage of Assets0.10.10.10.10.10.2
Percentage of Assets cms:CorporateAndReconcilingItems cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value15397149111449514396142371407913850140751390613429
Percentage of Assets56.155.655.756.957.457.457.960.460.362.1
Percentage of Assets56.155.655.756.957.457.457.960.460.362.1
Percentage of Assets us-gaap:OperatingSegments cms:ElectricUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-12-312018-12-312017-12-31
Value2640269220061453
Percentage of Assets9.610.08.26.3
Percentage of Assets9.610.08.26.3
Percentage of Assets us-gaap:OperatingSegments cms:EnerBank100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value553527500522524540538321342269
Percentage of Assets2.02.01.92.12.12.22.21.41.51.2
Percentage of Assets2.02.01.92.12.12.22.21.41.51.2
Percentage of Assets us-gaap:OperatingSegments cms:Enterprises100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value8678865983127890768178067513718771396446
Percentage of Assets31.632.332.031.231.031.831.430.831.029.8
Percentage of Assets31.632.332.031.231.031.831.430.831.029.8
Percentage of Assets us-gaap:OperatingSegments cms:GasUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-312017-12-31
Value154591497314557144591414313907
Percentage of Assets56.355.856.057.257.760.3
Percentage of Assets56.355.856.057.257.760.3
Percentage of Assets us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-312017-12-31
Value872587068359793778537139
Percentage of Assets31.832.432.131.432.031.0
Percentage of Assets31.832.432.131.432.031.0
Percentage of Assets us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value2744726837260092529224793245292391323312228682305022120218672162321622208422046320037203401945219238191981918518381177191792417416169861742917269171311660816293161601645215958159451564215616155711505115256
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value2420623699229382241622052220252149221283209492109920380202051982419946189801870218422186581797717867178541784716919163871631216179160941640916272162751580415554152671566215058151011495714839
Percentage of LiabilitiesAndStockholdersEquity88.288.388.288.688.989.889.991.391.691.592.192.491.792.291.191.491.991.792.492.993.093.092.092.591.092.994.794.194.295.095.295.594.595.294.494.795.695.0
Percentage of Assets88.288.388.288.688.989.889.991.391.691.592.192.491.792.291.191.491.991.792.492.993.093.092.092.591.092.994.794.194.295.095.295.594.595.294.494.795.695.0
Percentage of Assets cms:ConsumersEnergyCompany100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value870279797645
Percentage of LiabilitiesAndStockholdersEquity32.432.533.2
Percentage of Assets32.432.533.2
Percentage of Assets srt:ParentCompany100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value51855018495748514858475547494672459644414535444943704253425941564109393839023818380236703670364536183454339633233306319431963111304930283043295828872793282127092602
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets18.918.719.119.219.619.419.920.020.119.320.520.320.219.720.420.320.519.420.119.819.819.120.020.620.219.820.019.119.118.619.219.118.918.419.118.618.517.918.118.017.1

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value80667700769976107287688368866851667664516495642562095902592458795679550954855429547952405214521350584820480047544759453845594540445943504367430943104136
Percentage of StockholdersEquity155.6153.4155.3156.9150.0144.8145.0146.6145.3145.3143.2144.4142.1138.8139.1141.5138.2139.9140.6142.2144.1142.8142.1143.0139.8139.5141.3143.1144.0142.1142.6145.9146.2143.7143.5145.7149.3148.1
Percentage of Assets29.428.729.630.129.428.128.829.429.228.029.429.428.727.328.428.728.327.128.228.228.527.328.429.428.227.728.327.327.626.527.527.927.626.427.427.027.626.5
Percentage of Assets cms:ConsumersEnergyCompany33.332.533.633.933.031.332.032.231.930.631.931.831.329.631.231.430.829.530.530.430.729.430.831.831.029.829.829.029.227.928.829.229.227.829.028.528.827.9

Assets Current

us-gaap:AssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value28172331230522542376246823742286220724752121221122152280219820311890232021232291250125972734246529692526240124852528242223602206226825652860295627412759308626212742
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.38.78.98.99.610.19.99.89.710.79.610.110.210.510.59.99.411.410.911.913.013.514.913.916.614.514.114.314.614.114.213.514.015.617.918.517.517.719.817.418.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value22031872186517591794198017451825176619751790191217461942164715641549192918262038220822732256204922362157224421532216225522272110201624072563267926002519
Percentage of AssetsCurrent78.280.380.978.075.580.273.579.880.079.884.486.578.885.274.977.082.083.186.089.088.387.582.583.175.385.493.586.687.793.194.495.688.993.889.690.694.991.3
Percentage of Assets8.07.07.27.07.28.17.37.87.78.68.18.78.19.07.97.67.79.59.410.611.511.812.311.612.512.413.212.412.813.213.413.012.514.616.116.816.616.1
Percentage of Assets cms:ConsumersEnergyCompany9.17.98.17.88.19.08.18.68.49.48.89.58.89.78.78.48.410.310.211.412.412.713.312.513.713.313.913.113.613.914.113.613.215.417.017.717.417.0

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value3080147
Percentage of AssetsCurrent1.33.25.9
Percentage of Assets0.10.30.6
Percentage of Assets srt:ParentCompany0.31.01.9

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302008-12-312007-12-31
Value83414040331223415332347719518214241843323533938517726615047752220749335875817226053758693128187358161623994801247696536755901811023207344
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.00.51.51.20.90.61.42.00.90.80.61.92.01.11.61.90.91.30.82.52.71.12.72.04.21.01.53.13.40.50.81.12.21.03.96.25.11.64.53.60.00.60.00.00.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value604112591963739925411544553431821312111727504339742571200981781819928635555715417385373766713712333205913969
Percentage of CashAndCashEquivalentsAtCarryingValue72.47.964.362.815.825.52.853.259.024.238.782.142.055.76.230.415.318.828.783.281.434.340.627.423.510.576.553.360.65.444.582.448.352.859.977.189.028.733.559.778.343.333.3
Percentage of Assets2.20.01.00.80.10.20.01.10.50.20.21.60.80.60.10.60.10.20.22.12.20.41.10.61.00.11.21.62.10.00.30.91.10.52.34.84.60.51.52.10.00.30.0
Percentage of Assets cms:ConsumersEnergyCompany2.50.01.10.90.20.20.01.20.50.20.31.70.90.70.10.60.10.30.22.22.40.41.20.61.10.11.21.72.20.00.41.01.10.52.55.14.80.50.00.00.00.30.0

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value884886641749997964710708100210326316667758216346037307746406699088816837541032914678728914855667670750869690719930981672697948
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.23.32.53.04.03.93.03.04.44.52.93.03.63.83.02.93.63.83.33.54.74.63.74.35.85.24.04.25.35.04.04.14.65.34.34.55.96.34.34.66.2

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value7858276116538948556866908588856126487558006165857137586276558888636697391013902669719901844659659737860683706915963
Percentage of AccountsReceivableNetCurrent88.893.395.387.289.788.796.697.585.685.897.097.397.497.497.297.097.797.998.097.997.898.098.098.098.298.798.798.898.698.798.898.498.399.099.098.298.498.2
Percentage of Assets2.93.12.32.63.63.52.93.03.83.82.83.03.53.73.02.93.63.73.23.44.64.53.64.25.75.23.94.15.24.94.04.04.65.24.34.45.86.2
Percentage of Assets cms:ConsumersEnergyCompany3.23.52.72.94.13.93.23.24.14.23.03.23.84.03.23.13.94.13.53.75.04.84.04.56.25.64.24.45.55.24.24.24.85.54.54.76.16.5

Other Assets Current

us-gaap:OtherAssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value10186868397101103931018311811712081941029177878984727910811986687956536270505049373937393531
Percentage of OtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.30.30.30.40.40.40.40.40.40.50.50.60.40.50.50.50.40.40.50.40.40.40.60.70.50.40.50.30.30.40.40.30.30.30.20.20.20.30.20.2

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value857374718683908289711101101147085978466798378637310111177607250455663424343303027
Percentage of OtherAssetsCurrent84.284.986.085.588.782.287.488.288.185.593.294.095.086.490.495.192.385.790.893.392.987.592.493.593.389.588.291.189.384.990.390.084.086.087.881.176.973.0
Percentage of Assets0.30.30.30.30.30.30.40.40.40.30.50.50.50.30.40.50.40.30.40.40.40.30.40.60.60.40.40.40.30.30.30.40.30.30.30.20.20.2
Percentage of Assets cms:ConsumersEnergyCompany0.40.30.30.30.40.40.40.40.40.30.50.50.60.40.40.50.50.40.40.50.40.40.40.60.70.50.40.40.30.30.40.40.30.30.30.20.20.2

Property Plant And Equipment Gross

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value75637360726471307236703769096808668265106403631162066056595359225878574756975633554554155321524251685087535552785200512150474973500849014869480247314646461645664540
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets27.627.427.928.229.228.728.929.229.228.228.928.928.728.028.628.929.328.329.329.328.928.228.929.628.829.231.530.330.129.930.430.531.029.830.530.130.229.829.630.329.8

us-gaap:PublicUtility

cms:NonUtilityPlantAssets



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value91817163737066615754
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment1.21.21.11.01.31.31.31.21.21.2
Percentage of Assets0.30.30.30.30.40.40.40.40.30.3
Percentage of Assets cms:NonUtilityPlantAssets0.00.00.00.00.00.00.00.00.00.0

cms:UtilityPlantAssets



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value7269695664395993567453455021506048444592
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment98.898.898.999.098.798.798.798.898.898.8
Percentage of Assets27.128.427.927.727.927.928.829.529.429.4
Percentage of Assets cms:UtilityPlantAssets0.00.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value1914418926185241810618315181261779017237169041676116444161191585715715154431518714907147051416013775135261341212246
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets69.770.571.271.673.973.974.473.973.972.774.373.773.372.774.174.274.472.372.871.670.569.970.3

Investments In Affiliates Subsidiaries Associates And Joint Ventures

dei:LegalEntity

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value11112121202033343734292826283832343229293030323131293531313134
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.10.10.10.10.20.20.20.20.10.10.10.10.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.2
Percentage of Assets cms:ConsumersEnergyCompany0.00.00.00.00.10.10.10.10.20.20.20.20.20.20.10.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.2

Deferred Tax Assets Liabilities Net

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value723739492519538478629779789799269294321353258285315384288319354352335362392409233259283293217240268276203234252245178197254
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.62.81.92.12.21.92.63.33.53.51.21.31.51.61.21.41.61.91.51.71.81.81.82.02.22.31.41.51.61.71.31.51.71.71.31.51.61.61.11.31.7

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value619637407434458410545660674687160189218250151179209262165194230236208233263283149172198209134157179196123150174176
Percentage of OtherAssetsNoncurrent85.686.282.783.685.185.886.684.785.486.059.564.367.970.858.562.866.368.257.360.865.067.062.164.467.169.263.966.470.071.361.865.466.871.060.664.169.071.8
Percentage of Assets2.32.41.61.71.81.72.32.82.93.00.70.91.01.20.70.91.01.30.81.01.21.21.11.31.51.60.91.01.11.20.81.01.11.20.80.91.11.1
Percentage of Assets cms:ConsumersEnergyCompany2.62.71.81.92.11.92.53.13.23.30.80.91.11.30.81.01.11.40.91.11.31.31.21.41.61.70.91.01.21.30.81.01.21.30.81.01.21.2

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value16102
Percentage of OtherAssetsNoncurrent2.22.10.3
Percentage of Assets0.10.00.0
Percentage of Assets srt:ParentCompany0.20.10.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1



Period End2019-12-312018-12-31
Value0.01000000.0
Percentage of OtherAssetsNoncurrent0.00.2
Percentage of Assets0.00.0
Percentage of Assets us-gaap:FairValueInputsLevel10.00.0

Liabilities Current

us-gaap:LiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value29402704216523862106262434422535248227842261211519262655206920912047230217881640159920141648156318011945146418021645179714851807181923382214224122902021229717361954
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.710.18.39.48.510.714.410.910.912.110.29.78.912.39.910.210.211.39.28.58.310.59.08.810.011.28.610.39.510.58.911.111.314.213.914.114.612.914.811.512.8

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value16711712115612571298161823071635205621361679158314002094130315711511173113151146108013861161128813431480111711881286141011301274109016421383136312871161
Percentage of LiabilitiesCurrent56.863.353.452.761.661.767.064.582.876.774.374.872.778.963.075.173.875.273.569.967.568.870.482.474.676.176.365.978.278.576.170.559.970.262.560.856.257.4
Percentage of Assets6.16.44.45.05.26.69.67.09.09.37.67.26.59.76.37.77.58.56.86.05.67.26.37.37.58.56.66.87.48.26.87.86.710.08.78.58.27.4
Percentage of Assets cms:ConsumersEnergyCompany6.97.25.05.65.97.310.77.79.810.18.27.87.110.56.98.48.29.37.36.46.07.86.97.98.29.16.97.27.98.77.28.27.110.59.29.08.67.8

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value200332351
Percentage of LiabilitiesCurrent7.412.712.6
Percentage of Assets0.71.41.5
Percentage of Assets srt:ParentCompany2.34.24.6

Debt Current

us-gaap:ConsolidatedEntities

us-gaap:DebtCurrent

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value0180225
Percentage of DebtCurrent0.0100.0100.0
Percentage of Assets0.00.71.0
Percentage of Assets srt:ParentCompany0.02.32.9

Notes Payable Current

us-gaap:NotesPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312013-12-312012-12-31
Value0900030972790170230398752496860170110
Percentage of NotesPayableCurrent0.0100.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.30.00.00.10.41.20.00.71.01.80.41.20.30.31.00.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312013-12-312012-12-31
Value0900030972790170230398752496860170110
Percentage of NotesPayableCurrent0.0100.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.30.00.00.10.41.20.00.71.01.80.41.20.30.31.00.6
Percentage of Assets cms:ConsumersEnergyCompany0.00.40.00.00.10.41.30.00.81.12.00.41.30.40.31.10.7

Long Term Debt Current

us-gaap:LongTermDebtCurrent



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
Value17001111110011008219741900120013001081959819790864984897929684720498521519669418645541511737711519488631814103311161099726
Percentage of LongTermDebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.24.14.24.33.34.07.95.15.74.74.33.73.74.04.74.44.63.43.72.62.72.73.62.43.63.13.04.24.13.02.93.95.06.37.06.94.6

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value5022021022626268763766933434433733053752754484481982611001131246045444342422414140403933933833837
Percentage of LongTermDebtCurrent29.518.29.32.43.22.746.131.353.331.746.245.538.643.427.949.948.228.936.220.121.723.99.010.86.87.98.25.733.97.98.26.34.832.830.330.85.1
Percentage of Assets1.80.80.40.10.10.13.71.63.01.52.01.71.41.71.32.22.21.01.30.50.60.60.30.30.20.20.20.21.40.20.20.20.22.12.12.10.2
Percentage of Assets cms:ConsumersEnergyCompany2.10.90.40.10.10.14.11.83.31.62.21.81.51.91.42.42.41.11.50.60.60.70.40.30.30.30.30.31.50.30.30.30.32.22.22.20.2

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

cms:PalisadesPowerPurchaseAgreement, cms:FinancingObligation, cms:ConsumersEnergyCompany



Period End2019-12-31
Value13
Percentage of LongTermDebtCurrent1.2
Percentage of Assets0.0
Percentage of Assets cms:PalisadesPowerPurchaseAgreement cms:FinancingObligation cms:ConsumersEnergyCompany0.0

Accounts Payable Current

us-gaap:AccountsPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value490622598627544723680623534725624599479598539559534633586558512678604587632585519512426512491527409575484444413492456451509
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.82.32.32.52.22.92.82.72.33.12.82.72.22.82.62.72.73.13.02.92.73.53.33.33.53.43.12.92.53.03.03.22.53.53.02.82.63.22.93.03.3

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value458593569595515685636594514701601580465580521545521613571540496662591573611571508502414501480512396561473429403471
Percentage of AccountsPayableCurrent93.595.395.294.994.794.793.595.396.396.796.396.897.197.096.797.597.696.897.496.896.997.697.897.696.797.697.998.097.297.997.897.296.897.697.796.697.695.7
Percentage of Assets1.72.22.22.42.12.82.72.52.23.02.72.72.22.72.52.72.63.02.92.82.63.53.23.23.43.33.02.92.42.92.93.12.53.43.02.72.63.0
Percentage of Assets cms:ConsumersEnergyCompany1.92.52.52.72.33.13.02.82.53.32.92.92.32.92.72.92.83.33.23.02.83.73.53.53.73.53.23.12.53.13.03.32.63.63.12.82.73.2

Taxes Payable Current

us-gaap:TaxesPayableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value330437125295295398107267265360902562603489325225434990235239316892252252978820621127983199206282103239239302114230283
Percentage of TaxesPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.21.60.51.21.21.60.41.11.21.60.41.21.21.60.41.21.31.70.51.21.21.60.51.31.31.70.51.21.21.60.51.21.31.70.61.51.51.90.71.51.9

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value36348115829836943614827948454211125729135411426526235278166140149159283343353201316329376198271250287102163182199
Percentage of TaxesPayableCurrent110.0110.1126.4101.0125.1109.5138.3104.5182.6150.6123.3100.4111.9101.7122.6105.2103.1100.986.770.658.647.2178.7125.8152.4118.9228.4153.4155.9134.8238.6136.2121.4101.899.068.276.265.9
Percentage of Assets1.31.80.61.21.51.80.61.22.12.40.51.21.31.60.51.31.31.70.40.90.70.80.91.61.92.01.21.81.92.21.21.71.51.70.61.01.21.3
Percentage of Assets cms:ConsumersEnergyCompany1.52.00.71.31.72.00.71.32.32.60.51.31.51.80.61.41.41.90.40.90.80.80.91.72.12.21.21.92.02.31.31.71.61.80.71.11.21.3

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-31
Value50
Percentage of TaxesPayableCurrent1.10.0
Percentage of Assets0.00.0
Percentage of Assets srt:ParentCompany0.10.0

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value162186170182148147134117134195130145135199159127118142130123117163124129131146136139134152137136139159131122109144119117123
Percentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.60.70.70.70.60.60.60.50.60.80.60.70.60.90.80.60.60.70.70.60.60.80.70.70.70.80.80.80.80.90.80.80.91.00.80.80.70.90.80.80.8

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value10511812714211512096841031599310899164127938710910093901359997101112991009710910510810311994857695
Percentage of OtherLiabilitiesCurrent64.863.474.778.077.781.671.671.876.981.571.574.573.382.479.973.273.776.876.975.676.982.879.875.277.176.772.871.972.471.776.679.474.174.871.869.769.766.0
Percentage of Assets0.40.40.50.60.50.50.40.40.50.70.40.50.50.80.60.50.40.50.50.50.50.70.50.50.60.60.60.60.60.60.60.70.60.70.60.50.50.6
Percentage of Assets cms:ConsumersEnergyCompany0.40.50.60.60.50.50.40.40.50.80.50.50.50.80.70.50.50.60.60.50.50.80.60.60.60.70.60.60.60.70.70.70.70.80.60.60.50.6

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value3875
Percentage of OtherLiabilitiesCurrent20.44.82.6
Percentage of Assets0.10.00.0
Percentage of Assets srt:ParentCompany0.40.10.1

us-gaap:RestructuringCostAndReserve, us-gaap:RestructuringPlan

cms:RetentionAndSeveranceBenefits, cms:D.E.KarnGeneratingComplex



Period End2019-12-31
Value2
Percentage of OtherLiabilitiesCurrent1.1
Percentage of Assets0.0
Percentage of Assets cms:RetentionAndSeveranceBenefits cms:D.E.KarnGeneratingComplex0.0

cms:RetentionBenefits, cms:D.E.KarnGeneratingComplex



Period End2020-03-31
Value4
Percentage of OtherLiabilitiesCurrent2.5
Percentage of Assets0.0
Percentage of Assets cms:RetentionBenefits cms:D.E.KarnGeneratingComplex0.0

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value1928519078188501801817792171131568516068157531578815287152661529014677144771417913844140631372513743137601346413026124741246811980120891226712274120961188311331112481104210657107021042110758104081032210364
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets70.371.172.571.271.869.865.668.968.968.569.169.870.767.969.569.369.169.170.671.471.770.270.970.469.668.871.270.471.170.671.569.569.667.166.867.166.668.966.868.667.9

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value144321425014046135121343013487122621276012180124751216912160121781191311716112151119511381111401125511258111841050798499874984210140104301018310283100719696967496269264938593169498
Percentage of LiabilitiesNoncurrent74.874.774.575.075.578.878.279.477.379.079.679.779.681.280.979.180.980.981.281.981.883.180.779.079.282.283.985.083.085.084.885.686.087.286.987.789.488.3
Percentage of Assets52.653.154.053.454.255.051.354.753.354.155.055.656.355.156.254.855.956.057.358.558.658.357.255.655.156.559.759.859.060.060.659.559.958.558.158.959.660.8
Percentage of Assets cms:ConsumersEnergyCompany59.660.161.260.360.961.257.160.058.159.159.760.261.459.761.760.060.861.062.063.063.162.762.160.160.560.863.063.662.663.263.762.363.461.561.562.162.364.0

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value348428922853
Percentage of LiabilitiesNoncurrent18.316.918.1
Percentage of Assets13.011.812.4
Percentage of Assets srt:ParentCompany40.036.237.3

Long Term Debt

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value12545119511204011236111051061588699272899691239024909191298640872284868170844179038040814380168042753575367101708966956741671067116221619360406037618459266448601358835895
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets45.744.546.344.444.843.337.139.839.339.640.841.642.240.041.841.540.841.540.641.842.441.843.842.542.040.841.738.439.039.240.438.238.336.737.838.837.941.338.639.138.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value76167048708765466565677952395738521155615275533954195253536549224934520649695141515451545230455545674579459142764086429743083967397739873997416941794488
Percentage of LongTermDebtNoncurrent60.759.058.958.359.163.959.161.957.961.058.558.759.460.861.558.060.461.762.963.963.364.365.060.560.664.564.863.960.664.064.263.864.266.066.267.470.569.6
Percentage of Assets27.726.327.225.926.527.621.924.622.824.123.824.425.124.325.724.124.625.625.526.726.826.928.525.725.526.327.024.523.725.125.924.324.624.225.026.126.728.7
Percentage of Assets cms:ConsumersEnergyCompany31.529.730.929.229.830.824.427.024.926.425.926.427.326.328.326.326.827.927.628.828.928.930.927.828.028.328.526.125.126.427.325.526.025.526.527.627.930.2

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value333427502830
Percentage of LongTermDebtNoncurrent27.925.931.0
Percentage of Assets12.411.212.3
Percentage of Assets srt:ParentCompany38.334.537.0

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

cms:PalisadesPowerPurchaseAgreement, cms:FinancingObligation, cms:ConsumersEnergyCompany



Period End2019-12-31
Value16
Percentage of LongTermDebtNoncurrent0.1
Percentage of Assets0.1
Percentage of Assets cms:PalisadesPowerPurchaseAgreement cms:FinancingObligation cms:ConsumersEnergyCompany0.0

Deferred Tax Liabilities Noncurrent

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value14167444744344043679778777876676077078178956057058159184784684487224224124023974013931398145112911289128812891139113611351135128312761460
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.52.51.71.81.81.83.33.43.43.33.43.53.63.62.72.82.92.94.44.44.44.51.31.41.31.44.48.08.18.57.87.98.07.87.17.17.37.38.28.59.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value10362240440039639274173172171170371272373050051051952977076876679318318218017970213291334138512291227122512251081107810761076
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent73.092.390.490.390.089.993.092.992.792.892.592.592.692.589.389.589.389.590.990.890.890.975.675.575.074.994.995.495.495.595.295.295.195.094.994.994.894.8
Percentage of Assets0.42.31.61.61.61.63.13.13.23.13.23.33.33.42.42.52.62.64.04.04.04.11.01.01.01.04.17.67.78.17.47.57.67.46.86.86.96.9
Percentage of Assets cms:ConsumersEnergyCompany0.42.61.81.81.81.83.43.43.43.43.43.53.63.72.62.72.82.84.34.34.34.41.11.11.11.14.48.18.28.57.87.98.07.87.27.17.27.3

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value211721
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent3.13.92.7
Percentage of Assets0.10.10.1
Percentage of Assets srt:ParentCompany0.20.20.3

us-gaap:RetirementPlanType

us-gaap:PensionPlansDefinedBenefit



Period End2019-12-312018-12-312017-12-312016-12-31
Value531303618461
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent78.869.580.758.4
Percentage of Assets2.01.22.72.1
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.0

us-gaap:SupplementalEmployeeRetirementPlanDefinedBenefit



Period End2019-12-312018-12-312017-12-312016-12-31
Value140130145143
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent20.829.818.918.1
Percentage of Assets0.50.50.60.7
Percentage of Assets us-gaap:SupplementalEmployeeRetirementPlanDefinedBenefit0.00.00.00.0

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value517295
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent76.767.7
Percentage of Assets1.91.2
Percentage of Assets us-gaap:PensionPlansDefinedBenefit cms:ConsumersEnergyCompany0.00.0

us-gaap:SupplementalEmployeeRetirementPlanDefinedBenefit, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value10294
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent15.121.6
Percentage of Assets0.40.4
Percentage of Assets us-gaap:SupplementalEmployeeRetirementPlanDefinedBenefit cms:ConsumersEnergyCompany0.00.0

Minority Interest

us-gaap:MinorityInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value3737373737373737373737373737373737373737373737373737373744444444444444444444454597
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.30.30.30.30.30.30.30.30.30.30.30.30.6

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value395383373364345294295305307307308289295290283301314313299304304299307303307306316316311311323336328336265278288267278296310
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.41.41.41.41.21.21.31.31.31.41.31.41.31.41.51.61.51.51.61.61.61.71.71.71.81.91.81.81.81.92.12.02.01.71.71.81.71.82.02.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value311304298291274230233243244241241219223218212231243236239243241237243251253252260259253252252262254256178186187176
Percentage of OtherLiabilitiesNoncurrent78.779.479.979.979.478.279.079.779.578.578.275.875.675.274.976.777.475.479.979.979.379.379.282.882.482.482.382.081.481.078.078.077.476.267.266.964.965.9
Percentage of Assets1.11.11.11.21.10.91.01.01.11.01.11.01.01.01.01.11.21.21.21.31.31.21.31.41.41.41.51.51.51.51.51.61.61.61.11.21.21.1
Percentage of Assets cms:ConsumersEnergyCompany1.31.31.31.31.21.01.11.11.21.11.21.11.11.11.11.21.31.31.31.41.31.31.41.51.61.61.61.61.61.51.61.71.71.61.21.21.31.2

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value1792
Percentage of OtherLiabilitiesNoncurrent4.43.10.7
Percentage of Assets0.10.00.0
Percentage of Assets srt:ParentCompany0.20.10.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value51855018495748514858475547494672459644414535444943704253425941564109393839023818380236703670364536183454339633233306319431963111304930283043295828872793282127092602
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets18.918.719.119.219.619.419.920.020.119.320.520.320.219.720.420.320.519.420.119.819.819.120.020.620.219.820.019.119.118.619.219.118.918.419.118.618.517.918.118.017.1

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value80667700769976107287688368866851667664516495642562095902592458795679550954855429547952405214521350584820480047544759453845594540445943504367430943104136
Percentage of StockholdersEquity155.6153.4155.3156.9150.0144.8145.0146.6145.3145.3143.2144.4142.1138.8139.1141.5138.2139.9140.6142.2144.1142.8142.1143.0139.8139.5141.3143.1144.0142.1142.6145.9146.2143.7143.5145.7149.3148.1
Percentage of Assets29.428.729.630.129.428.128.829.429.228.029.429.428.727.328.428.728.327.128.228.228.527.328.429.428.227.728.327.327.626.527.527.927.626.427.427.027.626.5
Percentage of Assets cms:ConsumersEnergyCompany33.332.533.633.933.031.332.032.231.930.631.931.831.329.631.231.430.829.530.530.430.729.430.831.831.029.829.829.029.227.928.829.229.227.829.028.528.827.9

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value33333333333333333333333333333333333332222
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value51-25-83-182-166-271-278-346-383-531-434-512-511-616-607-706-744-855-881-949-936-1058-1080-1099-1110-1242-1276-1334-1346-1423-1426-1511-1548-1553-1542-1628-1675-1757-1731-1831-1927
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.2-0.1-0.3-0.7-0.7-1.1-1.2-1.5-1.7-2.3-2.0-2.3-2.4-2.8-2.9-3.5-3.7-4.2-4.5-4.9-4.9-5.5-5.9-6.2-6.2-7.1-7.5-7.7-7.8-8.3-8.6-9.3-9.6-9.4-9.7-10.2-10.7-11.3-11.1-12.2-12.6

cms:CumulativeEffectPeriodOfAdoption

cms:CumulativeEffectPeriodOfAdoptionAdjustmentPretax



Period End2020-01-01
Value-65
Percentage of RetainedEarningsAccumulatedDeficit0.0
Percentage of Assets0.0
Percentage of Assets cms:CumulativeEffectPeriodOfAdoptionAdjustmentPretax0.0

cms:CumulativeEffectPeriodOfAdoptionAdjustmentTax



Period End2020-01-01
Value14
Percentage of RetainedEarningsAccumulatedDeficit0.0
Percentage of Assets0.0
Percentage of Assets cms:CumulativeEffectPeriodOfAdoptionAdjustmentTax0.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1529151315041415141813641373134013151173121311431128106510871040967950931876925832797798810724711665667598611593515554569511512463
Percentage of RetainedEarningsAccumulatedDeficit2998.0-6052.0-1812.0-777.5-854.2-503.3-493.9-387.3-343.3-220.9-279.5-223.2-220.7-172.9-179.1-147.3-130.0-111.1-105.7-92.3-98.8-78.6-73.8-72.6-73.0-58.3-55.7-49.9-49.6-42.0-42.8-39.2-33.3-35.7-36.9-31.4-30.6-26.4
Percentage of Assets5.65.65.85.65.75.65.75.75.85.15.55.25.24.95.25.14.84.74.84.64.84.34.34.54.54.24.23.83.93.53.73.63.23.43.63.23.33.0
Percentage of Assets cms:ConsumersEnergyCompany6.36.46.66.36.46.26.46.36.35.66.05.75.75.35.75.65.25.15.24.95.24.74.74.95.04.54.44.14.13.73.93.83.43.53.83.43.43.1

us-gaap:StatementScenario, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementBusinessSegments

srt:ScenarioForecast, us-gaap:AccountingStandardsUpdate201613, cms:EnerBank



Period End2020-01-01
Value0.0
Percentage of RetainedEarningsAccumulatedDeficit0.0
Percentage of Assets0.0
Percentage of Assets srt:ScenarioForecast us-gaap:AccountingStandardsUpdate201613 cms:EnerBank0.0

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value-76-73-67-67-66-65-59-61-61-50-47-48-49-50-45-47-47-47-49-48-48-49-20-20-21-22-39-56-54-55-43-45-47-49-40-38-40-40-31-31-33
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.3-0.3-0.3-0.3-0.3-0.3-0.2-0.3-0.3-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.2-0.3-0.2-0.3-0.3-0.1-0.1-0.1-0.1-0.2-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.3-0.2-0.3-0.3-0.2-0.2-0.2

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312010-12-31
Value-28-28-20-20-21-21-27-29-29-12-8-8-9-3-3-1-3-6-11-12-11-722-2-9-9-6-8-1-4-20
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax36.838.429.929.931.832.345.847.547.524.017.016.718.46.06.72.16.412.822.425.022.914.3-10.0-10.09.123.116.111.114.52.28.54.1-0.0
Percentage of Assets-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1-0.1-0.00.00.0-0.0-0.1-0.1-0.0-0.0-0.0-0.0-0.00.0
Percentage of Assets cms:ConsumersEnergyCompany-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1-0.1-0.00.00.0-0.0-0.1-0.1-0.0-0.0-0.0-0.0-0.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value20139521056861713814970880646611725635841657
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues10.822.013.639.330.07.59.336.35.235.324.236.636.440.933.4

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value23835014149161919415772084648646713681867683
Percentage of NetCashProvidedByUsedInOperatingActivities118.488.667.186.4100.3140.6105.4101.7105.0100.3105.798.3107.2103.1104.0
Percentage of Revenues12.819.59.134.030.110.69.836.95.535.425.636.039.142.234.7
Percentage of Revenues cms:ConsumersEnergyCompany13.621.09.936.831.911.310.538.85.837.327.137.240.743.636.1

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-559-604-802-735-675-791-807-456-548-346-346-293-313-228-212
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-30.0-33.6-51.9-50.9-32.8-43.2-50.5-23.3-35.9-18.9-13.7-14.8-18.0-11.1-10.8

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-542-554-557-524-502-536-521-444-476-382-315-295-312-228-202
Percentage of NetCashProvidedByUsedInInvestingActivities97.091.769.571.374.467.864.697.486.9110.491.0100.799.7100.095.3
Percentage of Revenues-29.1-30.9-36.0-36.3-24.4-29.3-32.6-22.7-31.2-20.9-12.5-14.9-17.9-11.1-10.3
Percentage of Revenues cms:ConsumersEnergyCompany-31.1-33.2-39.0-39.3-25.8-31.3-34.7-23.9-33.1-22.0-13.2-15.4-18.6-11.5-10.7

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value1062-67691234150462523-229200-9432161-125-61221
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues57.0-3.744.716.27.325.332.7-11.713.1-5.112.73.1-7.2-3.011.2

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value904-52488181-109360126-195113-206-171-68-281371
Percentage of NetCashProvidedByUsedInFinancingActivities85.177.670.677.4-72.777.924.185.256.5219.1-53.3-111.5224.8-4.932.1
Percentage of Revenues48.5-2.931.612.5-5.319.77.9-10.07.4-11.3-6.8-3.4-16.10.13.6
Percentage of Revenues cms:ConsumersEnergyCompany51.8-3.134.113.6-5.621.08.4-10.57.9-11.9-7.2-3.5-16.80.23.8

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value20139521056861713814970880646611725635841657
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues10.822.013.639.330.07.59.336.35.235.324.236.636.440.933.4

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value23835014149161919415772084648646713681867683
Percentage of NetCashProvidedByUsedInOperatingActivities118.488.667.186.4100.3140.6105.4101.7105.0100.3105.798.3107.2103.1104.0
Percentage of Revenues12.819.59.134.030.110.69.836.95.535.425.636.039.142.234.7
Percentage of Revenues cms:ConsumersEnergyCompany13.621.09.936.831.911.310.538.85.837.327.137.240.743.636.1

Net Income Loss

us-gaap:NetIncomeLoss



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value16720793213108169139241-3172921997718612416410614867202969483204102126801446714810067411391001352514582886978
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues9.313.46.410.35.910.69.312.3-0.211.36.310.94.711.79.09.17.010.05.09.65.56.65.78.15.98.75.77.34.09.87.53.82.59.57.36.61.510.06.14.55.56.4

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value-102-13-15-24-15-26-82-17-18
Percentage of NetIncomeLoss-61.1-6.3-16.1-22.2-8.9-18.72733.3-9.9-19.6
Percentage of Revenues-5.7-0.8-1.0-1.3-0.9-1.7-4.6-1.1-1.2
Percentage of Revenues cms:CorporateAndReconcilingItems0.0-22.4-28.3-52.2-37.5-72.2-234.3-53.1-56.2

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value9122390671991306117694
Percentage of NetIncomeLoss54.5107.796.862.0117.893.5-2033.3102.3102.2
Percentage of Revenues5.114.46.23.712.48.73.411.56.5
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility8.617.88.86.215.211.95.614.18.7

us-gaap:OperatingSegments, cms:Enterprises



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value157101414-5487
Percentage of NetIncomeLoss9.03.410.80.92.410.11800.04.77.6
Percentage of Revenues0.80.50.70.10.30.9-3.00.50.5
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises23.411.917.21.47.023.0-94.713.812.7

us-gaap:OperatingSegments, cms:GasUtility



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value114-10864-19217259
Percentage of NetIncomeLoss68.3-4.88.659.3-11.215.1-2400.02.99.8
Percentage of Revenues6.4-0.60.63.5-1.21.44.00.30.6
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility18.7-5.62.610.1-10.16.912.02.63.2

Profit Loss

us-gaap:ProfitLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value24316820794213109169140241-2172931997818612516410714868202979484204102127811446714910167411401011352514684887580
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues13.09.413.46.510.36.010.69.412.3-0.111.36.410.94.811.79.19.17.110.05.09.65.56.65.78.15.98.85.87.34.09.97.63.82.59.67.46.61.510.16.34.55.96.5

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value2352062139822613118015224213618110421111719513217213516084215118119109221119153100162781631227667155921537916088107
Percentage of ProfitLoss96.7122.6102.9104.3106.1120.2106.5108.6100.4-6800.0105.2111.8106.0150.0104.8105.6104.9126.2108.1123.5106.4121.6126.6129.8108.3116.7120.5123.5112.5116.4109.4120.8113.4163.4110.791.1113.3316.0109.6104.8121.6
Percentage of Revenues12.611.513.86.811.07.211.310.212.47.611.97.211.57.112.39.69.68.910.86.210.26.78.37.48.86.910.67.18.24.710.89.24.44.110.66.77.44.711.16.65.4
Percentage of Revenues cms:ConsumersEnergyCompany13.512.314.97.311.67.712.010.913.08.112.67.612.17.513.010.210.09.411.36.610.67.18.87.99.37.111.07.58.44.911.39.54.54.311.17.17.74.911.76.95.7

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2020-03-312019-03-312018-03-31
Value-26-14-16
Percentage of ProfitLoss-10.7-6.6-6.6
Percentage of Revenues-1.4-0.7-0.8
Percentage of Revenues cms:CorporateAndReconcilingItems0.0-28.6-45.7

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-03-312018-03-31
Value118105139
Percentage of ProfitLoss48.649.357.7
Percentage of Revenues6.35.17.1
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility11.59.512.9

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-03-31
Value1411
Percentage of ProfitLoss5.85.2
Percentage of Revenues0.80.5
Percentage of Revenues us-gaap:OperatingSegments cms:EnerBank22.622.4

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-03-312018-03-31
Value20115
Percentage of ProfitLoss8.20.56.2
Percentage of Revenues1.10.00.8
Percentage of Revenues us-gaap:OperatingSegments cms:Enterprises34.51.523.8

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-03-312018-03-31
Value117121103
Percentage of ProfitLoss48.156.842.7
Percentage of Revenues6.35.95.3
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility16.314.413.3

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-03-31
Value118105
Percentage of ProfitLoss48.649.3
Percentage of Revenues6.35.1
Percentage of Revenues us-gaap:OperatingSegments cms:ElectricUtility cms:ConsumersEnergyCompany11.59.5

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-03-31
Value117121
Percentage of ProfitLoss48.156.8
Percentage of Revenues6.35.9
Percentage of Revenues us-gaap:OperatingSegments cms:GasUtility cms:ConsumersEnergyCompany16.314.4

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-03-312012-06-302012-03-312011-06-302011-03-312010-06-302010-03-31
Value2432079321316913924117292199186124164148672029483204144100671001358288
Percentage of ProfitLoss100.0100.098.9100.0100.099.3100.0100.098.9100.0100.099.2100.0100.098.5100.0100.098.8100.0100.099.0100.099.0100.097.6100.0
Percentage of Revenues13.013.46.410.310.69.312.311.36.310.911.79.09.110.05.09.66.65.78.17.37.53.87.36.66.14.5
Percentage of Revenues us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:RetainedEarnings, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value23520621398226131180152
Percentage of ProfitLoss96.7122.6102.9104.3106.1120.2106.5108.6
Percentage of Revenues12.611.513.86.811.07.211.310.2
Percentage of Revenues us-gaap:RetainedEarnings cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-03-312011-03-312010-03-31
Value316263215216298244206204279193197262183176238173169222153151199145137181138172162172
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Other Operating Capital Net

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-31
Value3-39147-6712-42100212410168-48-47
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-31
Value-181211022-15-2768-4811684-3-49-44
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet-600.0-30.874.8-32.8-125.064.368.0-2400.093.583.2-4.4102.193.6

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-171-93147111-209-90177-228-201-274-378-345-447-312-462-460
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-170-92148108-204-90173-226-197-270-374-338-442-302-458-459
Percentage of IncreaseDecreaseInInventories99.498.9100.797.397.6100.097.799.198.098.598.998.098.996.899.199.8

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-559-604-802-735-675-791-807-456-548-346-346-293-313-228-212
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-30.0-33.6-51.9-50.9-32.8-43.2-50.5-23.3-35.9-18.9-13.7-14.8-18.0-11.1-10.8

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-542-554-557-524-502-536-521-444-476-382-315-295-312-228-202
Percentage of NetCashProvidedByUsedInInvestingActivities97.091.769.571.374.467.864.697.486.9110.491.0100.799.7100.095.3
Percentage of Revenues-29.1-30.9-36.0-36.3-24.4-29.3-32.6-22.7-31.2-20.9-12.5-14.9-17.9-11.1-10.3
Percentage of Revenues cms:ConsumersEnergyCompany-31.1-33.2-39.0-39.3-25.8-31.3-34.7-23.9-33.1-22.0-13.2-15.4-18.6-11.5-10.7

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value523534597492481502700422365407348304274294191
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value520526596487476483480414361406345302273294186
Percentage of PaymentsToAcquirePropertyPlantAndEquipment99.498.599.899.099.096.268.698.198.999.899.199.399.6100.097.4

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value1062-67691234150462523-229200-9432161-125-61221
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues57.0-3.744.716.27.325.332.7-11.713.1-5.112.73.1-7.2-3.011.2

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-09-302017-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value904-52488181-109360126-195113-206-171-68-281371
Percentage of NetCashProvidedByUsedInFinancingActivities85.177.670.677.4-72.777.924.185.256.5219.1-53.3-111.5224.8-4.932.1
Percentage of Revenues48.5-2.931.612.5-5.319.77.9-10.07.4-11.3-6.8-3.4-16.10.13.6
Percentage of Revenues cms:ConsumersEnergyCompany51.8-3.134.113.6-5.621.08.4-10.57.9-11.9-7.2-3.5-16.80.23.8

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value1198756214629931723250250923301005502503900300
Percentage of ProceedsFromIssuanceOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-03-31
Value87375621297015620349
Percentage of ProceedsFromIssuanceOfLongTermDebt72.9100.0100.064.30.090.70.037.8

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value211566314790116545180475301126104591334
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value01303132158630330025011111031099
Percentage of RepaymentsOfLongTermDebt0.011.30.099.727.274.10.00.00.052.6100.042.3100.067.569.226.5
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value211566314790116545180475301126104591334
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value01303132158630330025011111031099
Percentage of RepaymentsOfLongTermDebt0.011.30.099.727.274.10.00.00.052.6100.042.3100.067.569.226.5
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ConsumersEnergyCompany0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument

us-gaap:DebtInstrumentInterestRateStatedPercentage

srt:ParentCompany, cms:FourPointSevenZeroZeroPercentSeniorNotesDue2043



Period End2019-12-31
Value0.047
Percentage of DebtInstrumentInterestRateStatedPercentage100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:FourPointSevenZeroZeroPercentSeniorNotesDue20430.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

srt:ParentCompany, cms:A5.625JuniorSubordinatedNotesDue2078, us-gaap:JuniorSubordinatedDebt



Period End2019-12-31
Value0.05625
Percentage of DebtInstrumentInterestRateStatedPercentage119.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:A5.625JuniorSubordinatedNotesDue2078 us-gaap:JuniorSubordinatedDebt0.0

srt:ParentCompany, cms:A5.875JuniorSubordinatedNotesDue2078, us-gaap:JuniorSubordinatedDebt



Period End2019-12-31
Value0.05875
Percentage of DebtInstrumentInterestRateStatedPercentage125.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:A5.875JuniorSubordinatedNotesDue2078 us-gaap:JuniorSubordinatedDebt0.0

srt:ParentCompany, cms:A5.875JuniorSubordinatedNotesDue2079, us-gaap:JuniorSubordinatedDebt



Period End2019-12-31
Value0.05875
Percentage of DebtInstrumentInterestRateStatedPercentage125.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:A5.875JuniorSubordinatedNotesDue2079 us-gaap:JuniorSubordinatedDebt0.0

srt:ParentCompany, cms:FivePointZeroFiveZeroPercentSeniorNotesDue2022, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.0505
Percentage of DebtInstrumentInterestRateStatedPercentage107.4
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:FivePointZeroFiveZeroPercentSeniorNotesDue2022 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:FourPointEightSevenFivePercentSeniorNotesDue2044, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.04875
Percentage of DebtInstrumentInterestRateStatedPercentage103.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:FourPointEightSevenFivePercentSeniorNotesDue2044 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:ThreePointEightSevenFivePercentSeniorNotesDue2024, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.03875
Percentage of DebtInstrumentInterestRateStatedPercentage82.4
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:ThreePointEightSevenFivePercentSeniorNotesDue2024 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:ThreePointFourFiveZeroPercentSeniorNotesDue2027, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.0345
Percentage of DebtInstrumentInterestRateStatedPercentage73.4
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:ThreePointFourFiveZeroPercentSeniorNotesDue2027 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:ThreePointSixZeroZeroPercentSeniorNotesDue2025, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.036
Percentage of DebtInstrumentInterestRateStatedPercentage76.6
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:ThreePointSixZeroZeroPercentSeniorNotesDue2025 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:ThreePointZeroZeroZeroPercentSeniorNotesDue2026, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.03
Percentage of DebtInstrumentInterestRateStatedPercentage63.8
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:ThreePointZeroZeroZeroPercentSeniorNotesDue2026 us-gaap:UnsecuredDebt0.0

srt:ParentCompany, cms:TwoPointNineFiveZeroPercentSeniorNotesDue2027A, us-gaap:UnsecuredDebt



Period End2019-12-31
Value0.0295
Percentage of DebtInstrumentInterestRateStatedPercentage62.8
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations srt:ParentCompany cms:TwoPointNineFiveZeroPercentSeniorNotesDue2027A us-gaap:UnsecuredDebt0.0

us-gaap:DebtInstrument, dei:LegalEntity

cms:FirstMortgageBondsDueAugust2051, cms:ConsumersEnergyCompany



Period End2020-03-31
Value0.035
Percentage of DebtInstrumentInterestRateStatedPercentage0.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FirstMortgageBondsDueAugust2051 cms:ConsumersEnergyCompany0.0

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

cms:FivePointEightZeroZeroPercentFirstMortgageBondsDue2035, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.058
Percentage of DebtInstrumentInterestRateStatedPercentage123.4
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FivePointEightZeroZeroPercentFirstMortgageBondsDue2035 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FivePointSixFiveZeroPercentFirstMortgageBondsDue2020, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0565
Percentage of DebtInstrumentInterestRateStatedPercentage120.2
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FivePointSixFiveZeroPercentFirstMortgageBondsDue2020 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FivePointThreeZeroZeroPercentFirstMortgageBondsDue2022, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.053
Percentage of DebtInstrumentInterestRateStatedPercentage112.8
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FivePointThreeZeroZeroPercentFirstMortgageBondsDue2022 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointNineSevenZeroPercentFirstMortgageBondsDue2040, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0497
Percentage of DebtInstrumentInterestRateStatedPercentage105.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointNineSevenZeroPercentFirstMortgageBondsDue2040 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointOneZeroZeroPercentFirstMortgageBondsDue2045, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.041
Percentage of DebtInstrumentInterestRateStatedPercentage87.2
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointOneZeroZeroPercentFirstMortgageBondsDue2045 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointThreeFiveZeroPercentFirstMortgageBondsDue2049, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0435
Percentage of DebtInstrumentInterestRateStatedPercentage92.6
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointThreeFiveZeroPercentFirstMortgageBondsDue2049 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointThreeFiveZeroPercentFirstMortgageBondsDue2064, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0435
Percentage of DebtInstrumentInterestRateStatedPercentage92.6
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointThreeFiveZeroPercentFirstMortgageBondsDue2064 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointThreeOneZeroPercentFirstMortgageBondsDue2042, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0431
Percentage of DebtInstrumentInterestRateStatedPercentage91.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointThreeOneZeroPercentFirstMortgageBondsDue2042 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointTwoEightZeroPercentFirstMortgageBondsDue2057, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0428
Percentage of DebtInstrumentInterestRateStatedPercentage91.1
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointTwoEightZeroPercentFirstMortgageBondsDue2057 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointZeroFiveZeroPercentFirstMortgageBondsDue2048, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0405
Percentage of DebtInstrumentInterestRateStatedPercentage86.2
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointZeroFiveZeroPercentFirstMortgageBondsDue2048 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:FourPointZeroOneZeroPercentFirstMortgageBondsDue2038, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0401
Percentage of DebtInstrumentInterestRateStatedPercentage85.3
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FourPointZeroOneZeroPercentFirstMortgageBondsDue2038 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:OnePointEightZeroZeroPercentTaxExemptRevenueBondsDue2049, cms:TaxExemptRevenueBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.018
Percentage of DebtInstrumentInterestRateStatedPercentage38.3
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:OnePointEightZeroZeroPercentTaxExemptRevenueBondsDue2049 cms:TaxExemptRevenueBonds cms:ConsumersEnergyCompany0.0

cms:SixPointOneSevenZeroPercentFirstMortgageBondsDue2040, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0617
Percentage of DebtInstrumentInterestRateStatedPercentage131.3
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:SixPointOneSevenZeroPercentFirstMortgageBondsDue2040 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointEightSixZeroPercentFirstMortgageBondsDue2052, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0386
Percentage of DebtInstrumentInterestRateStatedPercentage82.1
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointEightSixZeroPercentFirstMortgageBondsDue2052 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointEightZeroZeroPercentFirstMortgageBondsDue2028, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.038
Percentage of DebtInstrumentInterestRateStatedPercentage80.9
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointEightZeroZeroPercentFirstMortgageBondsDue2028 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointFiveTwoZeroPercentFirstMortgageBondsDue2037, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0352
Percentage of DebtInstrumentInterestRateStatedPercentage74.9
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointFiveTwoZeroPercentFirstMortgageBondsDue2037 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointNineFiveZeroPercentFirstMortgageBondsDue2043, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0395
Percentage of DebtInstrumentInterestRateStatedPercentage84.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointNineFiveZeroPercentFirstMortgageBondsDue2043 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointNineFiveZeroPercentFirstMortgageBondsDue2047, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0395
Percentage of DebtInstrumentInterestRateStatedPercentage84.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointNineFiveZeroPercentFirstMortgageBondsDue2047 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointOneEightZeroPercentFirstMortgageBondsDue2032, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0318
Percentage of DebtInstrumentInterestRateStatedPercentage67.7
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointOneEightZeroPercentFirstMortgageBondsDue2032 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointOneNineZeroPercentFirstMortgageBondsDue2024, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0319
Percentage of DebtInstrumentInterestRateStatedPercentage67.9
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointOneNineZeroPercentFirstMortgageBondsDue2024 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointOneTwoFivePercentFirstMortgageBondsDue2024, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.03125
Percentage of DebtInstrumentInterestRateStatedPercentage66.5
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointOneTwoFivePercentFirstMortgageBondsDue2024 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointOneZeroZeroPercentFirstMortgageBondsDue2050, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.031
Percentage of DebtInstrumentInterestRateStatedPercentage66.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointOneZeroZeroPercentFirstMortgageBondsDue2050 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointSevenFiveZeroPercentFirstMortgageBondsDue2050, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0375
Percentage of DebtInstrumentInterestRateStatedPercentage79.8
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointSevenFiveZeroPercentFirstMortgageBondsDue2050 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointSevenSevenZeroPercentFirstMortgageBondsDue2020, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0377
Percentage of DebtInstrumentInterestRateStatedPercentage80.2
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointSevenSevenZeroPercentFirstMortgageBondsDue2020 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointSixEightZeroPercentFirstMortgageBondsDue2027, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0368
Percentage of DebtInstrumentInterestRateStatedPercentage78.3
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointSixEightZeroPercentFirstMortgageBondsDue2027 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointThreeNineZeroPercentFirstMortgageBondsDue2027, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0339
Percentage of DebtInstrumentInterestRateStatedPercentage72.1
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointThreeNineZeroPercentFirstMortgageBondsDue2027 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointThreeSevenFivePercentFirstMortgageBondsDue2023, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.03375
Percentage of DebtInstrumentInterestRateStatedPercentage71.8
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointThreeSevenFivePercentFirstMortgageBondsDue2023 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:ThreePointTwoFiveZeroPercentFirstMortgageBondsDue2046, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0325
Percentage of DebtInstrumentInterestRateStatedPercentage69.1
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:ThreePointTwoFiveZeroPercentFirstMortgageBondsDue2046 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

cms:TwoPointEightFiveZeroPercentFirstMortgageBondsDue2022, cms:FirstMortgageBonds, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0285
Percentage of DebtInstrumentInterestRateStatedPercentage60.6
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:TwoPointEightFiveZeroPercentFirstMortgageBondsDue2022 cms:FirstMortgageBonds cms:ConsumersEnergyCompany0.0

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

cms:FirstMortgageBondsDueOctober2020, us-gaap:SubsequentEvent, cms:ConsumersEnergyCompany



Period End2020-04-27
Value0.0377
Percentage of DebtInstrumentInterestRateStatedPercentage0.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations cms:FirstMortgageBondsDueOctober2020 us-gaap:SubsequentEvent cms:ConsumersEnergyCompany0.0

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.10.0010000000000000009-0.0050000000000000044-0.00300000000000000270.184-0.00200000000000000180.00500000000000000440.1420.3250.3110.3310.340.3970.3880.367
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.158-0.00400000000000000360.00500000000000000440.00500000000000000440.1930.0060000000000000050.0090000000000000080.1540.3240.3230.3380.3440.3890.4060.372
Percentage of EffectiveIncomeTaxRateContinuingOperations158.0-400.0-100.0-166.7104.9-300.0180.0108.599.7103.9102.1101.298.0104.6101.4

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

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value1655148712692287201717482275201820451858
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value1864180916403042271024862350211721511986
Percentage of DeferredTaxLiabilities112.6121.7129.2133.0134.4142.2103.3104.9105.2106.9

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value66581188996276280278593510341240
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value429480533254126143180232261488
Percentage of DeferredTaxAssetsNet64.559.260.026.416.517.822.924.825.239.4

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value23191456541446265
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value34282156541435755
Percentage of UnrecognizedTaxBenefits147.8147.4150.0100.0100.0100.0100.0100.0100.075.091.984.6

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value2815542232019
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset



Period End2019-12-312019-09-302019-06-302019-03-31
Value47495154
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value40414446
Percentage of OperatingLeaseRightOfUseAsset85.183.786.385.2

Cash And Cash Equivalents Period Increase Decrease

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value861157433334267175366501227204173441463257368406288249
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value6282828421264563827614665853642121525013771112
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents72.917.865.663.524.032.010.455.164.331.949.182.545.859.113.633.724.745.0

Proceeds From Repayments Of Short Term Debt

us-gaap:StatementEquityComponents, dei:LegalEntity

cms:AdjustmentsToAdditionalPaidInCapitalStockholderContribution

us-gaap:AdditionalPaidInCapital, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value3500032535000150
Percentage of AdjustmentsToAdditionalPaidInCapitalStockholderContribution100.00.00.0100.0100.00.00.0100.0

us-gaap:StatementEquityComponents

cms:CommonStockReissuedValue

us-gaap:AdditionalPaidInCapital



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312013-03-312012-03-312011-09-302011-06-302011-03-312010-09-302010-03-31
Value00000002000155600500
Percentage of CommonStockReissuedValue0.00.00.00.00.00.00.0100.00.00.0100.0100.0100.00.00.0100.00.00.0

cms:EffectiveIncomeTaxRateReconciliationAMTSequestrationPercent



Period End2020-03-312019-03-31
Value-0.0330.0
Percentage of EffectiveIncomeTaxRateReconciliationAMTSequestrationPercent100.00.0

cms:EffectiveIncomeTaxRateReconciliationRegulatoryTaxBenefits



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value-0.0150.00.0-0.0150.0-0.05-0.043-0.047-0.049-0.054
Percentage of EffectiveIncomeTaxRateReconciliationRegulatoryTaxBenefits100.00.00.0100.00.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value-0.0190.0079999999999999980.007000000000000003-0.0250.0030000000000000027-0.048-0.042-0.042-0.044-0.048
Percentage of EffectiveIncomeTaxRateReconciliationRegulatoryTaxBenefits126.70.00.0166.70.096.097.789.489.888.9

cms:FinancingIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value676362565450434039
Percentage of FinancingIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value524354344
Percentage of FinancingIncome7.53.26.55.49.38.07.010.010.3

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value323133322
Percentage of FinancingIncome4.53.24.81.85.66.07.05.05.1

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-03-31
Value6249
Percentage of FinancingIncome92.590.7

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value201221022
Percentage of FinancingIncome3.00.01.63.63.72.00.05.05.1

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value32313332
Percentage of FinancingIncome4.53.24.81.85.66.07.05.0

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value20122102
Percentage of FinancingIncome3.00.01.63.63.72.00.05.0

us-gaap:SubsidiarySaleOfStock

cms:ForwardContractIndexedToIssuersEquityAggregateSalesPrice

us-gaap:ForwardContracts



Period End2020-03-31
Value150
Percentage of ForwardContractIndexedToIssuersEquityAggregateSalesPrice100.0

cms:InterestAndDividendIncomeRelatedParties



Period End2020-03-312019-03-31
Value70
Percentage of InterestAndDividendIncomeRelatedParties100.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302016-06-302014-09-302013-09-302012-09-302011-09-30
Value121111100011111
Percentage of InterestAndDividendIncomeRelatedParties14.30.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:LitigationCase

cms:LossContingencyNumberOfLawsuits

cms:ClassActionLawsuits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-31
Value4.00.00.00.04.00.00.04.04.04.0
Percentage of LossContingencyNumberOfLawsuits100.00.00.00.0100.00.00.0100.0100.0100.0

cms:IndividualLawsuits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-31
Value1.00.00.00.01.00.00.01.01.01.0
Percentage of LossContingencyNumberOfLawsuits25.00.00.00.025.00.00.025.025.025.0

us-gaap:StatementEquityComponents

cms:OtherChangesInNoncontrollingInterests

us-gaap:NoncontrollingInterest



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-09-302017-06-302016-06-302015-06-302014-06-302013-09-302013-06-302012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302009-09-302009-06-30
Value10110101111-1-8-1-10-1-10-1-1-4-3
Percentage of OtherChangesInNoncontrollingInterests100.00.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.0

cms:OtherNonoperatingIncomeExpenseRetirementBenefitsNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value312322232322222224343111010
Percentage of OtherNonoperatingIncomeExpenseRetirementBenefitsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value2921212221202120223239109
Percentage of OtherNonoperatingIncomeExpenseRetirementBenefitsNet93.591.395.595.791.390.995.590.991.7100.050.0100.081.8100.090.0

cms:PurchasedPowerRelatedParties



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value18221916182221191921212222212221172321222421232323202223202121212100
Percentage of PurchasedPowerRelatedParties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

dei:LegalEntity

cms:ReductionOfIncomeTaxExpense

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-31
Value500798141311
Percentage of ReductionOfIncomeTaxExpense100.00.00.0100.0100.0100.0100.0100.0100.0

us-gaap:TaxCreditCarryforward

cms:TaxCarryforwardAmountIncreaseDecrease

us-gaap:Research



Period End2020-03-31
Value9
Percentage of TaxCarryforwardAmountIncreaseDecrease100.0

us-gaap:TaxCreditCarryforward, dei:LegalEntity

us-gaap:Research, cms:ConsumersEnergyCompany



Period End2020-03-31
Value8
Percentage of TaxCarryforwardAmountIncreaseDecrease88.9

dei:LegalEntity

cms:UtilitiesOperatingExpensePurchasedPowerRelatedParties

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1822191618222219202323
Percentage of UtilitiesOperatingExpensePurchasedPowerRelatedParties100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalExpendituresIncurredButNotYetPaid



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value9535-155199-119102112173117116
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value8537-155385151290101154117116
Percentage of CapitalExpendituresIncurredButNotYetPaid89.5105.7100.0103.985.9-1500.063.288.290.289.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect



Period End2020-03-312019-03-31
Value70492
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-03-31
Value6008
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect85.28.7

us-gaap:CommonStockDividendsPerShareDeclared



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value0.40750.382500000000000060.38250.38250.38250.357499999999999930.35750.35750.35750.33250.33250.330.310.310.310.290.290.290.270.270.270.2550.2550.2550.240.240.240.210.210.210.150.150.150.1250.125
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConcentrationRiskByType, us-gaap:CreditScoreFico, us-gaap:StatementBusinessSegments

us-gaap:ConcentrationRiskPercentage1

us-gaap:CreditConcentrationRisk, cms:FICOScoreBetweenGoodAndExcellent, cms:EnerBank



Period End2020-03-31
Value0.85
Percentage of ConcentrationRiskPercentage1100.0

us-gaap:ProductOrService, us-gaap:ConcentrationRiskByType, us-gaap:StatementBusinessSegments

cms:LoansOriginatedWithinLastFiveYears, us-gaap:CreditConcentrationRisk, cms:EnerBank



Period End2020-03-31
Value0.97
Percentage of ConcentrationRiskPercentage1114.1

us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:VariableRate

us-gaap:DebtInstrumentBasisSpreadOnVariableRate1

srt:ParentCompany, cms:TermLoanFacilityDueFebruary2021, cms:TermLoanFacility, us-gaap:LondonInterbankOfferedRateLIBOR



Period End2020-03-31
Value0.005
Percentage of DebtInstrumentBasisSpreadOnVariableRate1100.0

us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:VariableRate

cms:TermLoanFacilityDueJanuary2021, cms:TermLoanFacility, us-gaap:LondonInterbankOfferedRateLIBOR



Period End2020-03-31
Value0.0045
Percentage of DebtInstrumentBasisSpreadOnVariableRate190.0

us-gaap:LongtermDebtType, us-gaap:StatementScenario

cms:TermLoanFacility, us-gaap:ScenarioForecast



Period End2022-10-31
Value0.0175
Percentage of DebtInstrumentBasisSpreadOnVariableRate10.0

us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

srt:ScenarioForecast, cms:TermLoanFacilityDue2025, cms:TermLoanFacility



Period End2022-10-31
Value0.0175
Percentage of DebtInstrumentBasisSpreadOnVariableRate10.0

us-gaap:LongtermDebtType, us-gaap:StatementScenario

us-gaap:DebtInstrumentInterestRateDuringPeriod

cms:TermLoanFacility, us-gaap:ScenarioForecast



Period End2022-10-31
Value0.04952
Percentage of DebtInstrumentInterestRateDuringPeriod100.0

us-gaap:StatementScenario, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

srt:ScenarioForecast, cms:TermLoanFacilityDue2025, cms:TermLoanFacility



Period End2022-10-31
Value0.04952
Percentage of DebtInstrumentInterestRateDuringPeriod100.0

us-gaap:DeferredIncomeTaxesAndTaxCredits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value676129174392303790689910287427342
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value440-42417835369623946442039-19
Percentage of DeferredIncomeTaxesAndTaxCredits65.70.0-13.8141.239.590.216.78.176.791.239.445.150.647.653.4-45.2

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value-4-6-7-6-7-4-3-4-4-7-8-8-5-6
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value-22-12-12-12-19-19-18-20-20-20-17-18
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses550.0171.4200.0171.4633.3475.0450.0285.7250.0250.0340.0300.0

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-4-6-7-6-7-4-4-4
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0133.3100.0

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-21-12-11-12-17-18
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses525.0171.4183.3171.4566.7450.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value-14-15-16-15-16-17-16-17-17-8-9-9-10-11
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value0.00.01000000.00.01000000.00.01000000.01000000.01000000.01000000.01000000.01000000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-0.0-0.0-6.7-0.0-6.2-0.0-5.9-12.5-11.1-11.1-10.0-9.1

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-14-15-15-16-15-16-17-16
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.093.8106.793.894.1106.294.1

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value0.00.01000000.00.01000000.00.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-0.0-0.0-6.7-0.0-6.2-0.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanContributionsByEmployer

us-gaap:PensionPlansDefinedBenefit



Period End2020-01-31
Value531
Percentage of DefinedBenefitPlanContributionsByEmployer100.0

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-01-31
Value518
Percentage of DefinedBenefitPlanContributionsByEmployer97.6

us-gaap:RetirementPlanType, us-gaap:SubsequentEventType

us-gaap:PensionPlansDefinedBenefit, us-gaap:SubsequentEvent



Period End2020-01-31
Value531
Percentage of DefinedBenefitPlanContributionsByEmployer100.0

us-gaap:RetirementPlanType, us-gaap:SubsequentEventType, dei:LegalEntity

us-gaap:PensionPlansDefinedBenefit, us-gaap:SubsequentEvent, cms:ConsumersEnergyCompany



Period End2020-01-31
Value518
Percentage of DefinedBenefitPlanContributionsByEmployer97.6

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value2522222222242425242223222221
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value484041403837373938383637
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets192.0181.8186.4181.8158.3148.0154.2177.3165.2172.7163.6176.2

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value2320212021232223
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets92.090.995.590.995.595.891.792.0

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value453838383534
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets180.0172.7172.7172.7145.8136.0

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value81011101079991313131211
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value2125242425232223222322222122
Percentage of DefinedBenefitPlanInterestCost262.5250.0218.2240.0250.0328.6244.4255.6244.4176.9169.2169.2175.0200.0

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value810101010889
Percentage of DefinedBenefitPlanInterestCost100.0100.090.9100.0100.0114.388.9100.0

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value202323232221
Percentage of DefinedBenefitPlanInterestCost250.0209.1230.0230.0244.4233.3

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value-23-17-17-18-17-26-24-24-24-5-6-5-10-11
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value77671617161716161314
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-30.4-41.2-33.3-41.2-66.7-70.8-66.7-340.0-266.7-320.0-130.0-127.3

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-21-16-16-16-16-23-23-22
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost91.394.194.188.994.188.595.891.7

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value87771716
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-34.8-41.2-38.9-41.2-70.8-66.7

us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value44334445455554
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-30
Value1210111010121212121211111010
Percentage of DefinedBenefitPlanServiceCost300.0250.0366.7333.3250.0300.0300.0240.0300.0240.0220.0220.0200.0250.0

us-gaap:RetirementPlanType, dei:LegalEntity

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value43343444
Percentage of DefinedBenefitPlanServiceCost100.075.0100.0133.375.0100.0100.080.0

us-gaap:PensionPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value121010101211
Percentage of DefinedBenefitPlanServiceCost300.0333.3333.3250.0300.0220.0

us-gaap:StatementEquityComponents

us-gaap:DividendsCommonStockCash

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value116109108109108101101102101949394878686808080757272686867636362535353-34-3534-28-28
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:RetainedEarnings, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value219196124100172139147126
Percentage of DividendsCommonStockCash188.8179.8114.891.7159.3137.6145.5123.5

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:DividendsPreferredStockCash

us-gaap:RetainedEarnings, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value1000000.00.01000000.01000000.00.01000000.0
Percentage of DividendsPreferredStockCash100.00.0100.0100.00.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.210.00.00.210.00.210.350.350.350.350.350.350.35
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.210.00.00.210.00.210.350.350.350.350.350.350.35
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-30
Value-0.0390.00100000000000000090.0-0.0350.00.0290.0
Percentage of EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate100.0100.00.0100.00.0100.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-30
Value-0.0340.00.0010000000000000009-0.0330.00100000000000000090.0290.0
Percentage of EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate87.20.00.094.30.0100.00.0

us-gaap:EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-302017-03-31
Value0.0280.00.00100000000000000090.0240.0029999999999999990.0150.00.01
Percentage of EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities100.00.0100.0100.0100.0100.00.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-302017-03-31
Value0.0140.0030000000000000010.0029999999999999990.010.00100000000000000090.0110.00100000000000000090.007
Percentage of EffectiveIncomeTaxRateReconciliationDeductionsQualifiedProductionActivities50.00.0300.041.733.373.30.070.0

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312011-03-31
Value-0.007-0.006-0.002-0.004-0.0040.003-0.01-0.011-0.018-0.005-0.0020.001
Percentage of EffectiveIncomeTaxRateReconciliationOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value-0.0030.0-0.001-0.003-0.0060.003-0.012-0.009-0.015-0.007-0.0090.0070.002
Percentage of EffectiveIncomeTaxRateReconciliationOtherAdjustments42.9-0.050.075.0150.0100.0120.081.883.3140.0450.00.0200.0

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.0460.00.00.0540.00299999999999999570.0570.0470.0410.0480.0490.0490.0420.034
Percentage of EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-31
Value0.0490.00.00100000000000000090.0560.00299999999999999570.0620.0450.0440.0470.0490.0480.0560.035
Percentage of EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes106.50.00.0103.7100.0108.895.7107.397.9100.098.0133.3102.9

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsResearch



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-302017-03-31
Value0.0340.00.00.002-0.0059999999999999980.0280.00.001
Percentage of EffectiveIncomeTaxRateReconciliationTaxCreditsResearch100.00.00.0100.0100.0100.00.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-09-302017-03-31
Value0.0310.00.00.002-0.0060000000000000020.0270.00.001
Percentage of EffectiveIncomeTaxRateReconciliationTaxCreditsResearch91.20.00.0100.0100.096.40.0100.0

us-gaap:FinanceLeaseInterestExpense



Period End2019-12-312019-09-302019-06-302019-03-31
Value5454
Percentage of FinanceLeaseInterestExpense100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value5454
Percentage of FinanceLeaseInterestExpense100.0100.0100.0100.0

us-gaap:FinanceLeaseInterestPaymentOnLiability



Period End2019-12-312019-09-302019-06-302019-03-31
Value5454
Percentage of FinanceLeaseInterestPaymentOnLiability100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value5454
Percentage of FinanceLeaseInterestPaymentOnLiability100.0100.0100.0100.0

us-gaap:FinanceLeasePrincipalPayments



Period End2019-12-312019-09-302019-06-302019-03-31
Value2212
Percentage of FinanceLeasePrincipalPayments100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value2212
Percentage of FinanceLeasePrincipalPayments100.0100.0100.0100.0

us-gaap:FinanceLeaseRightOfUseAssetAmortization



Period End2019-12-312019-09-302019-06-302019-03-31
Value0222
Percentage of FinanceLeaseRightOfUseAssetAmortization0.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value0222
Percentage of FinanceLeaseRightOfUseAssetAmortization0.0100.0100.0100.0

us-gaap:FuelCosts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value10310213011914213115011513214412511714597125161134167161154219165147154190126130199153152183151138140118
Percentage of FuelCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value3452-13-143334534414434335535424323-10
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value17252-107-25161284-1-7-37-1648313103-99-9-36
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value-31222-43-24659204-6-5-43-3343303102-100-6-31
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables-182.488.140.298.096.771.8600.071.4116.2206.289.696.899.0101.066.786.1

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value-5413-3441-8968-5-92-40-48-36105
Percentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value-5413-3539-8060-14-88-38-42-32108
Percentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0102.995.189.988.2280.095.795.087.588.9102.9

us-gaap:IncreaseDecreaseInTimeDeposits



Period End2020-03-312019-03-31
Value-7151
Percentage of IncreaseDecreaseInTimeDeposits100.0100.0

us-gaap:IncrementalCommonSharesAttributableToEquityForwardAgreements



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value100000000
Percentage of IncrementalCommonSharesAttributableToEquityForwardAgreements100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-30
Value00000000000111100000011111000000
Percentage of IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsCapitalizedAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value111111110011121111111
Percentage of InterestCostsCapitalizedAdjustment100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value111111110011121111111
Percentage of InterestCostsCapitalizedAdjustment100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value1920201916141410111088877776435345556666620878
Percentage of InterestExpenseOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value3444325454433334433232334445545196
Percentage of InterestExpenseOther15.820.020.021.118.814.335.740.045.540.050.037.537.542.942.957.157.150.075.066.760.066.775.060.080.080.066.783.383.366.783.395.075.0

us-gaap:InterestExpenseRelatedParty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value33330000
Percentage of InterestExpenseRelatedParty100.0100.0100.0100.00.00.00.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value33330000
Percentage of InterestExpenseRelatedParty100.0100.0100.0100.00.00.00.00.0

us-gaap:InvestmentIncomeInterestAndDividend



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302013-09-302013-06-302012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value122213242325121111111211142254554
Percentage of InvestmentIncomeInterestAndDividend100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302013-06-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value11211222222411111111211222445
Percentage of InvestmentIncomeInterestAndDividend100.050.0100.050.0100.066.7100.050.0100.066.7100.080.0100.050.0100.0100.0100.0100.0100.0100.0100.0100.0100.050.0100.0100.080.0100.0100.0

us-gaap:LeaseCost



Period End2019-12-312019-09-302019-06-302019-03-31
Value28283443
Percentage of LeaseCost100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value27283442
Percentage of LeaseCost96.4100.0100.097.7

us-gaap:LeaseIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value3942424248
Percentage of LeaseIncome100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value3942424248
Percentage of LeaseIncome100.0100.0100.0100.0100.0

us-gaap:IncomeTaxAuthorityName

us-gaap:LossContingencyDamagesSoughtValue

cms:EquatorialGuineaTaxAuthority



Period End2020-03-312019-09-302019-06-302019-03-31
Value15200152
Percentage of LossContingencyDamagesSoughtValue100.00.00.0100.0

us-gaap:OperatingLeaseCost



Period End2019-12-312019-09-302019-06-302019-03-31
Value3233
Percentage of OperatingLeaseCost100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value2232
Percentage of OperatingLeaseCost66.7100.0100.066.7

us-gaap:OperatingLeasePayments



Period End2019-12-312019-09-302019-06-302019-03-31
Value3323
Percentage of OperatingLeasePayments100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value2232
Percentage of OperatingLeasePayments66.766.7150.066.7

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302016-06-302015-09-302014-09-30
Value0.0-1000000.00.00.0-1000000.00.00.0-1000000.00.00.00.0-1000000.0-1000000.0-1000000.0
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax0.0100.00.00.0100.00.00.0100.00.00.00.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302016-06-302015-09-302014-09-30
Value0.0-1000000.00.00.0-1000000.00.00.0-1000000.00.00.00.0-1000000.0-1000000.0-1000000.0
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax0.0100.00.00.0100.00.00.0100.00.00.00.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302013-09-30
Value0.00.00.00.00.0-1000000.00.00.00.00.00.00.0-1000000.0
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax0.00.00.00.00.0100.00.00.00.00.00.00.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax



Period End2020-03-312019-09-302019-06-302019-03-31
Value-40-2-1
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax100.00.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent



Period End2020-03-312019-09-302019-06-302019-03-31
Value-40-2-1
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax100.00.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax



Period End2020-03-312019-09-302019-06-302019-03-31
Value-1000000.00.0-1000000.00.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax100.00.0100.00.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value-500-3-1
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.00.00.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302015-09-302015-03-312014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-30
Value-3-60-1-1-42001112-111117-21222-22
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.00.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-06-302014-03-312013-06-302013-03-312012-09-302012-06-302012-03-312011-06-30
Value0-8010620001-6-2231-1-422-3213-20
Percentage of OtherComprehensiveIncomeLossNetOfTax-0.0133.30.0-100.0-0.0-150.0100.00.00.00.0100.0-600.0-100.00.00.0-100.00.0-400.0200.0200.0150.0200.050.0150.0-100.00.0

dei:LegalEntity

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302018-12-312018-09-302018-06-302017-09-302017-06-302017-03-312015-03-312013-03-31
Value000-1000853
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax0.00.00.0100.00.00.00.0100.0100.0100.0

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302018-12-312018-09-30
Value0.00.00.0-1000000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax0.00.00.0100.0

dei:LegalEntity

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312015-03-31
Value0000000000-5-3
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax0.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302016-09-302016-06-302015-09-302015-06-302015-03-312014-09-302014-06-302013-09-302013-06-302013-03-312012-09-30
Value-1-10-1-1-1-1-1-10-1-1-1-2-1-1-1-1-1-1-1-1
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302015-09-302015-06-302015-03-312014-09-302014-06-302013-06-302013-03-312012-09-30
Value0.00.00.0-1000000.00.00.0-1000000.00.0-1000000.00.0-1000000.0-1000000.0-1000000.0-1000000.0-1000000.0-1000000.0-1000000.0-1000000.0-1000000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax-0.0-0.00.0100.0-0.0-0.0100.0-0.0100.00.0100.050.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302016-09-302016-06-302015-09-302015-06-302015-03-312014-09-302014-06-302013-09-302013-06-302013-03-312012-09-30
Value-1-10-1-1-1-1-1-10-1-1-1-2-1-1-1-1-1-1-1-1
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax100.0100.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents, dei:LegalEntity

us-gaap:AccumulatedDefinedBenefitPlansAdjustment, cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value0.00.0-1000000.00.0-1000000.00.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax-0.00.0100.0-0.0100.0-0.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302015-09-302015-06-302015-03-312014-06-302013-09-302013-06-30
Value0.01000000.00.00.00.01000000.00.00.00.01000000.00.01000000.01000000.01000000.01000000.01000000.01000000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax0.0100.00.00.00.0100.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302015-06-302013-09-302013-06-30
Value1000000.00.00.00.00.00.00.00.00.00.00.00.01000000.01000000.01000000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0

dei:LegalEntity

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-06-302014-09-302014-06-302014-03-312013-06-302013-03-312012-06-302012-03-312011-03-31
Value0000000-1002-223-2-112-443-3-1
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax0.00.00.00.00.00.00.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302015-09-302013-09-302012-09-302010-09-302010-06-302009-09-302009-06-30
Value00000000011-110040
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax0.00.00.00.00.00.00.00.00.0100.0100.0100.0100.00.00.0100.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302016-09-302016-06-302016-03-312015-06-302014-09-302014-06-302014-03-312013-06-302012-09-302012-03-312011-03-312010-09-302010-03-31
Value0000000001-112-1-11111-2-1-10
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax0.00.00.00.00.00.00.00.00.0100.00.00.00.00.00.00.00.00.0100.00.00.00.00.0

us-gaap:OtherCostAndExpenseOperating



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value315438313343354415366326310304315290290276293311312283329304266285304282295282295301288279273296275278306
Percentage of OtherCostAndExpenseOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNoncashIncomeExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value-947207-1625-25-10-21-21-19-19
Percentage of OtherNoncashIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-31
Value0828-2-220-18-7-22-17-17-16
Percentage of OtherNoncashIncomeExpense-0.017.0140.0-28.612.580.072.070.0104.881.089.584.2

us-gaap:OtherNonoperatingExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value450533349222264334431677331132332232203
Percentage of OtherNonoperatingExpense100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value35053214322226433443463331132332232
Percentage of OtherNonoperatingExpense75.0100.00.0100.0100.063.6100.033.3100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.025.085.742.9100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNonoperatingIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value0102101012022232332332233333549991139
Percentage of OtherNonoperatingIncome0.0100.00.0100.0100.00.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value01011100110142232312233227338358999
Percentage of OtherNonoperatingIncome0.0100.00.050.0100.00.00.00.0100.050.00.0700.0100.0100.0100.0100.0100.0400.0100.0100.0100.0100.0100.0233.3100.0100.0266.7100.0100.0200.0100.0100.0100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value2429562027444629142835281012201
Percentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value2229373726534130212728-11311251
Percentage of PaymentsForProceedsFromOtherInvestingActivities91.7100.066.1185.096.3120.589.1103.4150.096.480.0-3.6130.091.7125.0100.0

us-gaap:PaymentsOfOrdinaryDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value116110108110108102101103101
Percentage of PaymentsOfOrdinaryDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value219197124101172140147127119
Percentage of PaymentsOfOrdinaryDividends188.8179.1114.891.8159.3137.3145.5123.3117.8

us-gaap:PaymentsToAcquireLoansReceivable



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value4731581244610712075551
Percentage of PaymentsToAcquireLoansReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireNotesReceivable



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value836879912113878000-25
Percentage of PaymentsToAcquireNotesReceivable100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0

us-gaap:PensionAndOtherPostretirementBenefitContributions



Period End2020-03-312019-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value5310312681919135
Percentage of PensionAndOtherPostretirementBenefitContributions100.00.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value5180301671819125
Percentage of PensionAndOtherPostretirementBenefitContributions97.60.096.850.098.594.7100.092.6

dei:LegalEntity

us-gaap:PreferredStockDividendsAndOtherAdjustments

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-06-302015-12-312015-06-302014-12-312014-06-302013-09-302013-06-302012-09-302012-06-30
Value1000000.00.01000000.00.01000000.00.01000000.00.01000000.00.01000000.00.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.0
Percentage of PreferredStockDividendsAndOtherAdjustments100.00.0100.00.0100.00.0100.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:ProceedsFromContributedCapital

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-312011-03-312010-03-31
Value3500032535000100250150150150150150125200
Percentage of ProceedsFromContributedCapital100.00.00.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-31
Value1013333233363433241
Percentage of ProceedsFromIssuanceOfCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:SubsidiarySaleOfStock

cms:SettlementOfForwardContracts



Period End2020-03-31
Value97
Percentage of ProceedsFromIssuanceOfCommonStock96.0

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-31
Value-22-11-103-32-2-16-22-24-12-16-10-10
Percentage of ProceedsFromPaymentsForOtherFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-31
Value-101-93-54-7-6-9-1-6-5-5
Percentage of ProceedsFromPaymentsForOtherFinancingActivities45.5-9.190.0100.015.6-200.043.827.337.58.337.550.050.0

us-gaap:ProceedsFromSaleOfProductiveAssets



Period End2019-12-312018-12-31
Value1000000.00.0
Percentage of ProceedsFromSaleOfProductiveAssets100.00.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value1000000.00.0
Percentage of ProceedsFromSaleOfProductiveAssets100.00.0

us-gaap:ProvisionForDoubtfulAccounts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value54696632877
Percentage of ProvisionForDoubtfulAccounts100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value13232221112233332222211322212112112
Percentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value132322211122333322222113222121121
Percentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:StatementScenario

us-gaap:PublicUtilitiesApprovedRateIncreaseDecreaseAmount

cms:ConsumersEnergyCompany, cms:GasRateCase, us-gaap:ScenarioForecast



Period End2020-07-312019-07-31
Value109
Percentage of PublicUtilitiesApprovedRateIncreaseDecreaseAmount100.0100.0

us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:SubsequentEventType

us-gaap:RepaymentsOfDebt

srt:ParentCompany, cms:TermLoanFacilityDueJune2020TrancheOne, cms:TermLoanFacilityDueJune2020, us-gaap:SubsequentEvent



Period End2019-10-31
Value5
Percentage of RepaymentsOfDebt100.0

us-gaap:RepaymentsOfShortTermDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-06-302018-03-312017-12-312017-09-30
Value90-9003067017060-230
Percentage of RepaymentsOfShortTermDebt100.0100.00.0100.0100.00.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-06-302018-03-312017-12-312017-09-30
Value90-9003067017060-230
Percentage of RepaymentsOfShortTermDebt100.0100.00.0100.0100.00.0100.0100.0100.0

us-gaap:RestructuringCostAndReserve, us-gaap:RestructuringPlan

us-gaap:RestructuringCharges

cms:RetentionBenefits, cms:D.E.KarnGeneratingComplex



Period End2020-03-31
Value4
Percentage of RestructuringCharges100.0

us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueNewIssues

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value1061081075739878083970172910783778297238722656443
Percentage of StockIssuedDuringPeriodValueNewIssues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:StockRepurchasedDuringPeriodValue

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-03-312015-03-312014-09-302014-03-312013-09-302013-06-302012-09-302011-09-302011-06-302010-09-302010-06-302009-09-302009-06-30
Value12110800010011211011169-19-60-1-1-10
Percentage of StockRepurchasedDuringPeriodValue100.0100.0100.00.0100.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0

us-gaap:TaxesExcludingIncomeAndExciseTaxes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-312009-09-302009-06-30
Value114867071106816768876266816260875960815756755450705348693351674941665148
Percentage of TaxesExcludingIncomeAndExciseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpense

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value14151362111011591615148112311166152113231129
Percentage of UtilitiesOperatingExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseDepreciationAndAmortization

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value312259210212294240203201277226191
Percentage of UtilitiesOperatingExpenseDepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseFuelUsed

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value798010188106971228610294115
Percentage of UtilitiesOperatingExpenseFuelUsed100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseGasAndPetroleumPurchased

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value270217321044012894510837725142
Percentage of UtilitiesOperatingExpenseGasAndPetroleumPurchased100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseMaintenanceAndOperations

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value278364272320319373334298282289274
Percentage of UtilitiesOperatingExpenseMaintenanceAndOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

us-gaap:UtilitiesOperatingExpensePurchasedPower

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value347338408350374381440388378424369331445360343389337346382348484374340329379327313362299293359310277
Percentage of UtilitiesOperatingExpensePurchasedPower100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity

cms:PowerSupplyCostRecovery, cms:ConsumersEnergyCompany



Period End2019-10-312019-03-31
Value19002000
Percentage of UtilitiesOperatingExpensePurchasedPower0.0534.8

dei:LegalEntity

us-gaap:UtilitiesOperatingExpenseTaxes

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value111826869103796566857360
Percentage of UtilitiesOperatingExpenseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:VariableLeaseCost



Period End2019-12-312019-09-302019-06-302019-03-31
Value20202431
Percentage of VariableLeaseCost100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312019-09-302019-06-302019-03-31
Value20202431
Percentage of VariableLeaseCost100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:VariableLeaseIncome

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-03-31
Value2534
Percentage of VariableLeaseIncome100.0100.0

us-gaap:WeightedAverageNumberOfSharesIssuedBasic



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-30
Value28302832822820282282281280279278278278276276275274274268266264264263262261255251250250229228
Percentage of WeightedAverageNumberOfSharesIssuedBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:AccrualForEnvironmentalLossContingenciesInflationRate

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.025
Percentage of AccrualForEnvironmentalLossContingenciesInflationRate100.0

cms:AccruedRateRefunds



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312010-09-302010-06-302009-12-31
Value42351834254144546333577732133413426202723612201221
Percentage of AccruedRateRefunds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value42351834254144546333577732133413426202723612
Percentage of AccruedRateRefunds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity

cms:GasCostRecovery, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value20
Percentage of AccruedRateRefunds5.70.0

cms:PowerSupplyCostRecovery, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value334
Percentage of AccruedRateRefunds94.3100.0

cms:AssetsNoncurrentOtherThanPropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value548655805180493241023935374937893757381435553537355136273201324532403315316931723176
Percentage of AssetsNoncurrentOtherThanPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-31
Value321532572905291023022284232223722415249422642287233524012006206620802141207221352237
Percentage of AssetsNoncurrentOtherThanPropertyPlantAndEquipment58.658.456.159.056.158.061.962.664.365.463.764.765.866.262.763.764.264.665.467.370.4

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value867278997498
Percentage of AssetsNoncurrentOtherThanPropertyPlantAndEquipment155.4200.7196.6

cms:DebtInstrumentSupportedByThirdPartyCreditEnhancement



Period End2020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value3535353535103103103103103103103103103103103103103103103103103103103103103103103103103103103103
Percentage of DebtInstrumentSupportedByThirdPartyCreditEnhancement100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value3535353535353535103103103103103103103103103103103103103103103103103103103103103103103103103103103103103
Percentage of DebtInstrumentSupportedByThirdPartyCreditEnhancement100.0100.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

cms:DeferredPropertyTaxes



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
Value246305184204226279167187207257157179203250152174193235141159178216202
Percentage of DeferredPropertyTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



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
Value246305184204226279167187207257157179203250152174193235141159178216202
Percentage of DeferredPropertyTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cms:DeferredTaxAssetsNetOperatingLossAndTaxCreditCarryforwards



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value239385453871657676629733806
Percentage of DeferredTaxAssetsNetOperatingLossAndTaxCreditCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value20641011904645486167
Percentage of DeferredTaxAssetsNetOperatingLossAndTaxCreditCarryforwards8.416.622.321.87.06.77.68.38.3

cms:DeferredTaxAssetsOperatingLossAndCreditCarryforwards



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value239385453871657676-629-733-806-996
Percentage of DeferredTaxAssetsOperatingLossAndCreditCarryforwards100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value20641011904645-48-61-67-281
Percentage of DeferredTaxAssetsOperatingLossAndCreditCarryforwards8.416.622.321.87.06.77.68.38.328.2

cms:DeferredTaxLiabilitiesPostretirementBenefits



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value172165961581277299
Percentage of DeferredTaxLiabilitiesPostretirementBenefits100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value178172105181156103119
Percentage of DeferredTaxLiabilitiesPostretirementBenefits103.5104.2109.4114.6122.8143.1120.2

us-gaap:RetirementPlanName

cms:DefinedContributionPlanTrustAssetsAmount

cms:SupplementalEmployeeRetirementPlanDefinedContribution



Period End2019-12-312018-12-312017-12-31
Value855
Percentage of DefinedContributionPlanTrustAssetsAmount100.0100.0100.0

us-gaap:ConsolidatedEntities

cms:FederalIncomeTaxesReceivableCurrent

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value184477
Percentage of FederalIncomeTaxesReceivableCurrent100.0100.0100.0

cms:FinanceLeaseLiabilityAndOtherNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value717681869169
Percentage of FinanceLeaseLiabilityAndOtherNoncurrent100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value717681869169
Percentage of FinanceLeaseLiabilityAndOtherNoncurrent100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:FinanceLeaseRightOfUseAssetAccumulatedAmortization

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value239212
Percentage of FinanceLeaseRightOfUseAssetAccumulatedAmortization100.0100.0

dei:LegalEntity

cms:FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-31
Value340309312
Percentage of FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization100.0100.0100.0

us-gaap:PublicUtility, dei:LegalEntity

cms:ElectricAssetsHeldUnderFinanceLeases, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value326295
Percentage of FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization95.995.5

us-gaap:ConsolidatedEntities

cms:InvestmentInSubsidiariesParentOnly

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value852677067202
Percentage of InvestmentInSubsidiariesParentOnly100.0100.0100.0

cms:LongTermDebtCurrentMaturitiesLeaseObligationAndOtherFinancingCurrent



Period End2020-03-312019-12-31
Value17211130
Percentage of LongTermDebtCurrentMaturitiesLeaseObligationAndOtherFinancingCurrent100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-31
Value521221
Percentage of LongTermDebtCurrentMaturitiesLeaseObligationAndOtherFinancingCurrent30.319.6

cms:LongTermDebtCurrentMaturitiesLeaseObligationCurrentAndOtherFinancingCurrent



Period End2019-12-312018-12-31
Value1130996
Percentage of LongTermDebtCurrentMaturitiesLeaseObligationCurrentAndOtherFinancingCurrent100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value22148
Percentage of LongTermDebtCurrentMaturitiesLeaseObligationCurrentAndOtherFinancingCurrent19.64.8

us-gaap:PublicUtilitiesRegulatoryProceeding, dei:LegalEntity

cms:NetOverUnderRecoveryOfExpenseIncludingInterestAuthorized

cms:PowerSupplyCostRecovery, cms:ConsumersEnergyCompany



Period End2019-10-312019-03-31
Value32-31
Percentage of NetOverUnderRecoveryOfExpenseIncludingInterestAuthorized100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

cms:NonqualifiedDeferredCompensationPlanAssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-31
Value171817161514665554
Percentage of NonqualifiedDeferredCompensationPlanAssetsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity

us-gaap:FairValueInputsLevel1, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1314131210
Percentage of NonqualifiedDeferredCompensationPlanAssetsFairValueDisclosure76.577.876.575.071.4

us-gaap:FairValueByFairValueHierarchyLevel

cms:NonqualifiedDeferredCompensationPlanLiabilitiesFairValueDisclosure

us-gaap:FairValueInputsLevel1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value171817161514665555554446
Percentage of NonqualifiedDeferredCompensationPlanLiabilitiesFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity

us-gaap:FairValueInputsLevel1, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1314131210
Percentage of NonqualifiedDeferredCompensationPlanLiabilitiesFairValueDisclosure76.577.876.575.071.4

us-gaap:ConsolidatedEntities

cms:NotesPayableIntercompanyPayablesAndRelatedPartyPayables

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value1121160
Percentage of NotesPayableIntercompanyPayablesAndRelatedPartyPayables100.0100.00.0

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

cms:NotesReceivableRelatedPartiesFairValueDisclosure

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value103103104105106
Percentage of NotesReceivableRelatedPartiesFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, dei:LegalEntity

us-gaap:CarryingReportedAmountFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value103103104105106
Percentage of NotesReceivableRelatedPartiesFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value103103104105106
Percentage of NotesReceivableRelatedPartiesFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:NumberOfFormerManufacturedGasPlants

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value23.0
Percentage of NumberOfFormerManufacturedGasPlants100.0

us-gaap:RetirementPlanType

cms:PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax

cms:PensionAndDBSERP



Period End2019-12-312018-12-312017-12-312016-12-31
Value111497810171062
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax100.0100.0100.0100.0

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-12-312018-12-312017-12-312016-12-31
Value308402316483
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax27.641.131.145.5

us-gaap:RetirementPlanType, dei:LegalEntity

cms:PensionAndDBSERP, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value1114978
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax100.0100.0

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value308402
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetGainsLossesBeforeTax27.641.1

us-gaap:RetirementPlanType

cms:PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax

cms:PensionAndDBSERP



Period End2019-12-312018-12-312017-12-312016-12-31
Value891115
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-12-312018-12-312017-12-312016-12-31
Value-300-361-451-187
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax-3750.0-4011.1-4100.0-1246.7

us-gaap:RetirementPlanType, dei:LegalEntity

cms:PensionAndDBSERP, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value89
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax100.0100.0

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value-300-361
Percentage of PensionAndOtherPostretirementBenefitPlansRegulatoryAssetsLiabilitiesNetPriorServiceCostCreditBeforeTax-3750.0-4011.1

cms:PropertyPlantAndEquipmentGrossExcludingCWIP



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-312012-12-31
Value256752539024645242632472924400237512325822878225062196621628212652101020698204971933418943185471821717930177211618415592
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

cms:CorporateAndReconcilingItems



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value21204544424240403830
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP0.10.10.20.20.20.20.20.20.20.1

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, cms:ElectricUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value16338161581581215660161961602715772156461522114540
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP63.663.664.264.565.565.766.467.367.669.2

us-gaap:OperatingSegments, cms:EnerBank



Period End2020-03-312019-12-312018-12-312017-12-31
Value22222521
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP0.10.10.10.1

us-gaap:OperatingSegments, cms:Enterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value407405406405404412405175167157
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP1.61.61.61.71.61.71.70.80.70.7

us-gaap:OperatingSegments, cms:GasUtility



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value8887878583828154808779197534739770806283
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP34.634.634.033.632.732.531.731.831.529.9

us-gaap:PublicUtility

cms:EnterprisesIpp



Period End2019-12-312018-12-312017-12-31
Value403410163
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP1.61.70.7

cms:EnterprisesOther



Period End2019-12-312018-12-312017-12-31
Value224
Percentage of PropertyPlantAndEquipmentGrossExcludingCWIP0.00.00.0

cms:PropertyPlantAndEquipmentNetExcludingCWIP



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
Value1811218030173811713317493173631684216450161961599615563153171505914954147451457513456131961285012584123851230611097
Percentage of PropertyPlantAndEquipmentNetExcludingCWIP100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-31
Value187881857017761
Percentage of PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization100.0100.0100.0

dei:LegalEntity

cms:PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-312017-12-31
Value25246249632396322318
Percentage of PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress100.0100.0100.0100.0

us-gaap:ConsolidationItems, dei:LegalEntity

cms:CorporateAndReconcilingItems, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-312017-12-31
Value21201717
Percentage of PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress0.10.10.10.1

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

us-gaap:OperatingSegments, cms:ElectricUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-312017-12-31
Value16338161581602715221
Percentage of PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress64.764.766.968.2

us-gaap:OperatingSegments, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-312017-12-31
Value8887878579197080
Percentage of PublicUtilitiesPropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortizationAndConstructionWorkInProgress35.235.233.031.7

dei:LegalEntity

cms:PublicUtilitiesPropertyPlantAndEquipmentNetExcludingCWIP

cms:ConsumersEnergyCompany



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
Value1777517691170391678717144170051648816323160801587715449152051494914844146351446313344131211277412510123111223411022
Percentage of PublicUtilitiesPropertyPlantAndEquipmentNetExcludingCWIP100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:PublicUtilitiesPropertyPlantandEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312018-12-31
Value747172726958
Percentage of PublicUtilitiesPropertyPlantandEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization100.0100.0100.0

us-gaap:PublicUtility, dei:LegalEntity

cms:NonUtilityPlantAssets, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value32
Percentage of PublicUtilitiesPropertyPlantandEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization0.00.0

cms:UtilityPlantAssets, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value72696956
Percentage of PublicUtilitiesPropertyPlantandEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization100.0100.0

us-gaap:RetirementPlanType

cms:TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost

cms:PensionAndDBSERP



Period End2019-12-312018-12-312017-12-312016-12-31
Value1227107711261171
Percentage of TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost100.0100.0100.0100.0

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit



Period End2019-12-312018-12-312017-12-312016-12-31
Value-634-153282
Percentage of TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost-0.53.2-13.624.1

us-gaap:RetirementPlanType, dei:LegalEntity

cms:PensionAndDBSERP, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value11581014
Percentage of TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost94.494.2

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value841
Percentage of TotalAmountsNotYetRecognizedAsComponentOfNetPeriodicBenefitCost0.73.8

cms:UnionMembershipByTotalEmployeesPercentage



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value0.350.350.380.390.40.410.430.43
Percentage of UnionMembershipByTotalEmployeesPercentage100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value0.370.370.40.410.420.430.450.45
Percentage of UnionMembershipByTotalEmployeesPercentage105.7105.7105.3105.1105.0104.9104.7104.7

dei:EntityCommonStockSharesOutstanding



Period End2020-04-062020-01-102019-10-072019-07-092019-04-082019-01-142018-10-092018-07-11
Value286283283283283283283283
Percentage of EntityCommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:AccountsReceivableFairValueDisclosure

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value19202120212222212021222018222321
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1920212022
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value19202120212222212021222018222321
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value19202120212222212021222018222321
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementBasis, dei:LegalEntity

us-gaap:CarryingReportedAmountFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1920212022
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1920212022
Percentage of AccountsReceivableFairValueDisclosure100.0100.0100.0100.0100.0

us-gaap:AccountsReceivableGrossCurrent



Period End2019-12-312018-12-312017-12-312016-12-31
Value13141412
Percentage of AccountsReceivableGrossCurrent100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value1314
Percentage of AccountsReceivableGrossCurrent100.0100.0

us-gaap:FairValueByAssetClass, dei:LegalEntity

cms:OtherReceivables, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value1313141414
Percentage of AccountsReceivableGrossCurrent0.0100.00.00.0100.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingencies

cms:BayHarbor



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value4646444545464647484849505151525354585960616263505152
Percentage of AccrualForEnvironmentalLossContingencies100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:CerclaLiability, cms:ConsumersEnergyCompany



Period End2019-12-31
Value3
Percentage of AccrualForEnvironmentalLossContingencies6.5

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value68
Percentage of AccrualForEnvironmentalLossContingencies147.8

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value677068
Percentage of AccrualForEnvironmentalLossContingencies145.7159.1151.1

cms:Nrepa, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2019-12-31
Value1000000.0
Percentage of AccrualForEnvironmentalLossContingencies2.2

us-gaap:Range, us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

srt:Maximum, cms:Nrepa, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-30
Value1311
Percentage of AccrualForEnvironmentalLossContingencies2.26.52.32.2

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

us-gaap:AccrualForEnvironmentalLossContingenciesDiscountRate

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value0.0257
Percentage of AccrualForEnvironmentalLossContingenciesDiscountRate100.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesGross

cms:BayHarbor



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value5758565657585858596162636465676869747577788082686971
Percentage of AccrualForEnvironmentalLossContingenciesGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value73
Percentage of AccrualForEnvironmentalLossContingenciesGross125.9

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value727274
Percentage of AccrualForEnvironmentalLossContingenciesGross126.3128.6132.1

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInFifthYear

cms:BayHarbor



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
Value444444444444444444555554
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFifthYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value2
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFifthYear50.0

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value2112
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFifthYear50.0275.050.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInFourthYear

cms:BayHarbor



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
Value444444444444444445555554
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFourthYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value11
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFourthYear275.0

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value11207
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInFourthYear275.0500.0175.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInRemainderOfFiscalYear

cms:BayHarbor



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-30
Value42231231345667778
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInRemainderOfFiscalYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value1238
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInRemainderOfFiscalYear300.0150.0400.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInSecondYear

cms:BayHarbor



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
Value445444444444445555666665
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInSecondYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value8
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInSecondYear200.0

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value81316
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInSecondYear200.0260.0400.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueInThirdYear

cms:BayHarbor



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
Value444444444444444445555565
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInThirdYear100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value20
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInThirdYear500.0

us-gaap:EnvironmentalRemediationSite, us-gaap:PublicUtility, dei:LegalEntity

cms:ManufacturedGasPlant, cms:GasUtility, cms:ConsumersEnergyCompany



Period End2020-03-312019-09-302019-06-30
Value201221
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueInThirdYear500.0300.0525.0

us-gaap:EnvironmentalRemediationSite

us-gaap:AccrualForEnvironmentalLossContingenciesUndiscountedDueWithinOneYear

cms:BayHarbor



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value5455686
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueWithinOneYear100.0100.0100.0100.0100.0100.0100.0

us-gaap:EnvironmentalRemediationSite, dei:LegalEntity

cms:ManufacturedGasPlant, cms:ConsumersEnergyCompany



Period End2019-12-31
Value12
Percentage of AccrualForEnvironmentalLossContingenciesUndiscountedDueWithinOneYear240.0

us-gaap:AccumulatedDeferredInvestmentTaxCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value1191201161179899101102868788897273747355565657583738393940414142434444454647474849484951
Percentage of AccumulatedDeferredInvestmentTaxCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1191201161179899101102868788897273747355565657583738393940414142434444454647474849
Percentage of AccumulatedDeferredInvestmentTaxCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdditionalPaidInCapitalCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value52075113510450975087508850835076503750195013500649274916490849064897483748294812478347744767476147464715470847104703466946624664464146274622462145994588458145694560
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value57245374537453745049469946994699454944494449444942493999399939993874372437243724372435743574357234073257325732573257310731073107310729572957295729572832
Percentage of AdditionalPaidInCapitalCommonStock109.9105.1105.3105.499.392.492.492.690.388.688.788.986.281.381.581.579.177.077.177.477.974.975.075.071.869.169.269.269.366.566.666.666.963.964.064.064.361.7

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value2220212020202020192022222424272729283337374036363333313131323035353525252525232323
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value2220212020202020192022222424272729283336363934343131292929302833333323232323
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.097.397.397.594.494.493.993.993.593.593.593.893.394.394.394.392.092.092.092.0

us-gaap:AllowanceForNotesAndLoansReceivableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-31
Value3333332826242323212019181716121010998
Percentage of AllowanceForNotesAndLoansReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForNotesAndLoansReceivableNoncurrent



Period End2020-03-312019-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value6608886555555555555555556
Percentage of AllowanceForNotesAndLoansReceivableNoncurrent100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligation



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value477432430447439419340325312254245229
Percentage of AssetRetirementObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cms:AssetRetirementObligationsCategories

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Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value0.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.0
Percentage of AssetRetirementObligation0.00.20.20.20.20.20.30.30.30.40.40.4

cms:RenewableGenerationAssets



Period End2019-12-312018-12-312017-12-31
Value330
Percentage of AssetRetirementObligation0.60.70.0

cms:AssetRetirementObligationsCategories, dei:LegalEntity

cms:AsbestosAbatement, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value343342565453514943424038
Percentage of AssetRetirementObligation7.17.69.812.512.312.615.015.113.816.516.316.6

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Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value166179191201200192120118114706664
Percentage of AssetRetirementObligation34.841.444.445.045.645.835.336.336.527.626.927.9

cms:GasDistributionCutPurgeCap, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value231205186182178167162154151140136124
Percentage of AssetRetirementObligation48.447.543.340.740.539.947.647.448.455.155.554.1

cms:GasWellsPlugAndAbandon, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-31
Value220
Percentage of AssetRetirementObligation4.60.0

cms:RenewableGenerationAssets, cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-31
Value2111107
Percentage of AssetRetirementObligation4.42.52.31.6

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value474428429446438418339324311253244228
Percentage of AssetRetirementObligation99.499.199.899.899.899.899.799.799.799.699.699.6

us-gaap:AssetRetirementObligationsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value485477451438433432421426427430443452451447445442440439419348344340330329328325322319316312264261257254254252249245237235229
Percentage of AssetRetirementObligationsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value482474448435430428417425426429442451450446444441439438418347343339329328327324321318315311263260257253253251248244
Percentage of AssetRetirementObligationsNoncurrent99.499.499.399.399.399.199.099.899.899.899.899.899.899.899.899.899.899.899.899.799.799.799.799.799.799.799.799.799.799.799.699.6100.099.699.699.699.699.6

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel12And3



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1353649586864
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, dei:LegalEntity

us-gaap:FairValueInputsLevel12And3, cms:ConsumersEnergyCompany



Period End2020-03-312019-12-312019-09-302019-06-302018-12-31
Value3833413129
Percentage of AssetsFairValueDisclosure28.191.783.753.445.3

us-gaap:ConsolidatedEntities

us-gaap:AvailableForSaleSecuritiesDebtSecuritiesNoncurrent

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value4325
Percentage of AvailableForSaleSecuritiesDebtSecuritiesNoncurrent100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:FairValueInputsLevel1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value9100182027871003394855360141271109512875183
Percentage of CashAndCashEquivalentsFairValueDisclosure100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConstructionInProgressGross



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value10328961143973822763948787708765881802798761698612145115091310119111411106121113391206114994311081135108011341011899783672644627570605643506
Percentage of ConstructionInProgressGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption

us-gaap:RetainedEarnings



Period End2020-01-012019-07-012019-04-012019-01-012018-07-012018-06-302018-04-012018-03-312018-01-012017-12-312017-06-302017-03-312017-01-012016-12-312015-12-31
Value-510000008880003333
Percentage of CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption100.00.00.00.00.00.00.0100.0100.0100.00.00.00.0100.0100.0

us-gaap:DebtInstrumentCarryingAmount



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value131881168310265956491378547765472457093
Percentage of DebtInstrumentCarryingAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:LegalEntity

cms:ConsumersEnergyCompany



Period End2019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value7322686259405661540952834625434143294529
Percentage of DebtInstrumentCarryingAmount55.558.757.959.259.261.860.459.961.00.0

us-gaap:ConsolidatedEntities

srt:ParentCompany



Period End2019-12-312018-12-312017-12-31
Value338529653080
Percentage of DebtInstrumentCarryingAmount25.725.430.0

us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

srt:ParentCompany, cms:A5.875JuniorSubordinatedNotesDue2079, us-gaap:JuniorSubordinatedDebt



Period End2019-12-312018-12-31
Value6300
Percentage of DebtInstrumentCarryingAmount4.80.0

srt:ParentCompany, cms:RevolvingCreditFacilitiesTwo, us-gaap:RevolvingCreditFacility



Period End2019-12-312018-12-312017-12-31
Value0300
Percentage of DebtInstrumentCarryingAmount0.00.30.0

srt:ParentCompany, cms:TermLoanFacilityDueDecember2019, cms:TermLoanFacility



Period End2019-12-312018-12-31
Value0180
Percentage of DebtInstrumentCarryingAmount0.01.5

us-gaap:ConsolidatedEntities, us-gaap:LongtermDebtType

srt:ParentCompany, cms:TermLoanFacility



Period End2019-12-312018-12-312017-12-31
Value0210405
Percentage of DebtInstrumentCarryingAmount0.01.83.9

srt:ParentCompany, us-gaap:JuniorSubordinatedDebt



Period End2019-12-312018-12-312017-12-31
Value11104800
Percentage of DebtInstrumentCarryingAmount8.44.10.0

srt:ParentCompany, us-gaap:UnsecuredDebt



Period End2019-12-312018-12-312017-12-31
Value227522752675
Percentage of DebtInstrumentCarryingAmount17.319.526.1

us-gaap:DebtInstrument, us-gaap:LongtermDebtType

cms:TermLoanFacilityDue2025, cms:TermLoanFacility



Period End2019-12-312018-12-31
Value9298
Percentage of DebtInstrumentCarr