FE


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents


us-gaap:StatementEquityComponents
us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:CostsAndExpenses

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

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

us-gaap:InterestAndDebtExpense
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:InterestExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:NetIncomeLoss
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NonoperatingIncomeExpense

us-gaap:OperatingIncomeLoss

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

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

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

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

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:AccountsReceivableNetCurrent
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType
us-gaap:AccountsNotesLoansAndFinancingReceivablesByBillingStatusType

us-gaap:InventoryNet

us-gaap:OtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross
us-gaap:StatementBusinessSegments

us-gaap:ConstructionInProgressGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

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

us-gaap:LongTermInvestments

us-gaap:Goodwill
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:FiniteLivedIntangibleAssetsNet
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent

us-gaap:AccountsPayableCurrent

us-gaap:AccruedIncomeTaxesCurrent

us-gaap:LiabilitiesCurrent

us-gaap:LongTermDebtCurrent

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherLiabilitiesCurrent

us-gaap:LiabilitiesNoncurrent
dei:LegalEntity, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongTermDebt
us-gaap:ConsolidatedEntities, us-gaap:StatementBusinessSegments
us-gaap:DebtInstrument
us-gaap:FairValueByMeasurementBasis

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:DepreciationDepletionAndAmortization

us-gaap:IncreaseDecreaseInInventories

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquireProductiveAssets
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:ProceedsFromIssuanceOfLongTermDebt
us-gaap:FairValueByMeasurementBasis

us-gaap:RepaymentsOfLongTermDebt
us-gaap:FairValueByMeasurementBasis

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:DeferredTaxLiabilities

us-gaap:UnrecognizedTaxBenefits

fe:AmortizationDeferralOfRegulatoryAsset
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

fe:AmountPaidtoSettleAgreementsandTaxSharingPaymentstoSubsidiaryDebtors
fe:AssetAcquisition, us-gaap:StatementBusinessSegments
fe:AssetAcquisitionOwnershipInterestAcquired
us-gaap:LossContingenciesByNatureOfContingency
fe:CappingOfGasOneEmissionsUnderCrossStateAirPollutionRule
us-gaap:LossContingenciesByNatureOfContingency
fe:CappingOfGasTwoEmissionsUnderCrossStateAirPollutionRule

fe:CollateralPostedDueToCreditRatingDowngrade

fe:DebtandEquitySecuritiesRealizedGainLossSalesProceeds

fe:DebtandEquitySecuritiesRealizedGains

fe:DebtandEquitySecuritiesRealizedLosses
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
fe:DeconsolidationGainLossAmountBeforeTax
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
fe:DeconsolidationSettlementConsiderationandServicesCredit

fe:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationIncreaseDecreaseinDiscountRate
us-gaap:RetirementPlanType
fe:DefinedBenefitPlanBenefitObligationOneTimeTerminationBenefit
us-gaap:RetirementPlanType
fe:DefinedBenefitPlanNetPeriodicBenefitCostExcludingCapitalizedAmounts

fe:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryReturnSeekingAssetsSoldDuringPeriod

fe:DefinedBenefitPlanPlanAssetsPeriodIncreaseDecreaseIncludingDiscontinuedOperations

fe:DiscontinuedOperationTaxEffectOfDiscontinuedOperationAdjustmentsRelatedToIntercompanyTaxSharing
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
fe:DisposalGroupIncludingDiscontinuedOperationFuelCosts
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
fe:DisposalGroupIncludingDiscontinuedOperationOtherOperatingExpenses
us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:ValuationTechnique
fe:FairValueInputsRTOAuctionClearingPrices
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityPurchases
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitySettlements
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityUnrealizedGainLoss
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisUnrealizedGainLoss
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
fe:IncomeTaxExpenseBenefitfromDeconsolidationGainLossIncludingWorthlessStockDeduction
us-gaap:RetirementPlanType
fe:IncreaseDecreasetoNetPeriodicBenefitCostBasedonMarktoMarketAdjustment

fe:InvestmentIncomeFromTrusts
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments
fe:PublicUtilitiesExpectedCostOfTheProgram
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments
fe:PublicUtilitiesNumberOfMetersToBeDeployed
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
fe:PublicUtilitiesPlantConstructionPlantCapacity
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding
fe:PublicUtilitiesProgramStudyFindingsSubmittedAmount
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
fe:PublicUtilitiesRecoveryOfDeferredIncrementalUncollectibleAndOtherRelatedCosts
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
fe:PublicUtilitiesRequestedAnnualRateIncreaseDecreaseAmount
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency
fe:PublicUtilitiesSettledDecreaseInRegulatoryLiability
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency
fe:PublicUtilitiesSettledRevenueIncreaseAmount
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
fe:TaxCutsandJobsActChangeinTaxRateRefundofRevenue
us-gaap:StatementBusinessSegments

us-gaap:AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease
us-gaap:PublicUtilitiesRegulatoryProceeding

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DeconsolidationGainOrLossAmount

us-gaap:DeferredIncomeTaxesAndTaxCredits
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:Depreciation
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:DisposalGroupClassification, us-gaap:PublicUtility, us-gaap:StatementBusinessSegments
us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax

us-gaap:DiscontinuedOperationTaxEffectOfDiscontinuedOperation
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DisposalGroupIncludingDiscontinuedOperationOtherIncome
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DisposalGroupIncludingDiscontinuedOperationRevenue

us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents

us-gaap:ExciseTaxesCollected
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

us-gaap:FuelCosts

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare

us-gaap:IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable

us-gaap:IncreaseDecreaseInEmployeeRelatedLiabilities

us-gaap:IncreaseDecreaseInInterestPayableNet

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestCostsCapitalized

us-gaap:InterestCostsCapitalizedAdjustment
us-gaap:MajorCustomers
us-gaap:LateFeeIncomeGeneratedByServicingFinancialAssetsAmount

us-gaap:NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic

us-gaap:NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic

us-gaap:OtherComprehensiveIncomeLossBeforeTax
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax

us-gaap:OtherComprehensiveIncomeLossTax
us-gaap:StatementEquityComponents

us-gaap:OtherCostAndExpenseOperating
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForRemovalCosts

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt

us-gaap:PensionAndOtherPostretirementBenefitExpense
dei:LegalEntity, us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:ProceedsFromLongTermLinesOfCredit
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
dei:LegalEntity
us-gaap:PublicUtilitiesApprovedDebtCapitalStructurePercentage
dei:LegalEntity
us-gaap:PublicUtilitiesApprovedEquityCapitalStructurePercentage
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesApprovedRateIncreaseDecreaseAmount
dei:LegalEntity
us-gaap:PublicUtilitiesApprovedReturnOnEquityPercentage
dei:LegalEntity, us-gaap:StatementBusinessSegments, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:StatementGeographical
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreasePercentage

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax
us-gaap:StatementEquityComponents

us-gaap:RepaymentsOfShortTermDebt
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesEmployeeBenefitPlan

us-gaap:StockIssuedDuringPeriodValueEmployeeBenefitPlan
us-gaap:StatementEquityComponents

us-gaap:UtilitiesOperatingExpensePurchasedPower

us-gaap:UtilitiesOperatingExpenseTaxes

fe:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale
us-gaap:StatementBusinessSegments

fe:AdversePowerContractLiability

fe:AllowanceForLoanAndLossDeferredRecoveryOfBadDebts
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
fe:AmountOfImpairmentToCarryingAmountOfRegulatoryAssetsNet
dei:LegalEntity, fe:AssetAcquisition, us-gaap:StatementGeographical, us-gaap:StatementBusinessSegments
fe:AssetAcquisitionRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAssets

fe:CashandCashEquivalentsHeldforSaleFairValueDisclosure

fe:CompanyPostedCollateralRelatedToNetLiabilityPositions
us-gaap:StatementBusinessSegments, us-gaap:StatementScenario
fe:DeactivatedPowerPlantsCapacity

fe:DebtInstrumentUnamortizedMergerFairValueAdjustments

fe:DebtSecuritiesHeldforsale

fe:DeferredChargesandOtherAssetsNoncurrent

fe:DeferredIncomeTaxLiabilitiesNetNoncurrent

fe:DeferredTaxAssetsLiabilitiesNetAssetRetirementObligationLiability

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardValuationReserve

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardsAndTaxCredits

fe:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpirationNetOfTax

fe:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpirationNetOfTax

fe:DefinedBenefitPlanMarktoMarketAdjustmentNet
dei:LegalEntity

fe:DisposalGroupIncludingDiscontinuedOperationInvestments
fe:LossContingenciesByClaims
fe:EnvironmentalLiabilitiesFormerGasFacilities
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding
fe:ExpendituresForCostRecoveryProgram
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
fe:FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:ValuationTechnique
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
fe:FairValueOfAssetsLiabilitiesNet
us-gaap:FairValueByMeasurementFrequency

fe:FinancingLeaseRightofUseAssetAccumulatedAmortization
dei:LegalEntity, fe:BusinessUnits, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
fe:InvestmentOwnershipPercentagePledgedAsCollateral
dei:LegalEntity, fe:BusinessUnits, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

fe:InvestmentsExcludesReceivablesPayablesDeferredTaxesAndAccruedIncome
us-gaap:RetirementPlanType
fe:InvestmentsFinancialInstrumentsReceivablesPayablesTaxesAndAccruedIncome

fe:InvestmentsNotRequiredToBeDisclosed

fe:LeaseObligations

fe:LeasedAsset

fe:LesseeLeaseLiability

fe:LesseeLeaseLiabilityPaymentsDue

fe:LesseeLeaseLiabilityPaymentsDueAfterYearFive

fe:LesseeLeaseLiabilityPaymentsDueYearFive

fe:LesseeLeaseLiabilityPaymentsDueYearFour

fe:LesseeLeaseLiabilityPaymentsDueYearThree

fe:LesseeLeaseLiabilityPaymentsDueYearTwo

fe:LesseeLeaseLiabilityPaymentsImputedInterest

fe:LesseeLeaseLiabilityPaymentsNextTwelveMonths

fe:LesseeOperatingLeaseLeaseNotyetCommencedAmount

fe:LesseeOperatingLeaseResidualValueGuaranteePotentialLoss

fe:NetPlantExcludingConstructionWorkInProgress

fe:NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale
us-gaap:StatementBusinessSegments

fe:NetRegulatoryAssetsInvestmentReturnToBeRecovered

fe:NuclearFuelDisposalTrust

fe:OperatingLeaseRightofUseAssetAccumulatedAmortization

fe:OperatingLossCarryforwardsExpectedToUtilizedNetofTax
dei:LegalEntity, us-gaap:StatementBusinessSegments
fe:PlantCapacity
us-gaap:StatementBusinessSegments

fe:PrepaidTaxesandOther

fe:PretaxNetOperatingLossCarryforwardsExpectedToUtilized

fe:PropertyPlantAndEquipmentExcludingConstructionInProgress

fe:PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale
us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementGeographical, us-gaap:StatementScenario
fe:PublicUtilityCapacityShortfall
us-gaap:CreditFacility, us-gaap:Range, us-gaap:ShortTermDebtType, us-gaap:StatementScenario
fe:RatioofInterestCoverage

fe:ReductioninPowerPlantsCarbonPollutionPercentage
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
fe:RegulatoryAssetRecoveryAssessmentsLostDistributionRevenue

fe:RemainingAmountsOfRegulatoryAssetsTorWhichAreBeingSoughtForRecoveryInAFormulaRateAmendment

fe:RemainingAmountsofRegulatoryAssetsforwhichRecoveryisBasedonPriorPrecedentorRateMakingwithoutaSpecificOrder
us-gaap:StatementBusinessSegments
fe:ServiceArea

fe:UnrecognizedTaxBenefitsPortionExpectedToBeResolvedInNextFiscalYear

fe:UnrecognizedTaxBenefitsthatWouldImpactEffectiveTaxRateFutureYears
us-gaap:ConsolidatedEntities, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyOne
us-gaap:ConsolidatedEntities, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyTwo
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType
us-gaap:AccountsReceivableGrossCurrent
fe:LossContingenciesByClaims
us-gaap:AccrualForEnvironmentalLossContingencies

us-gaap:AccruedEmployeeBenefitsCurrent

us-gaap:AllowanceForDoubtfulAccountsReceivable
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType
us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
us-gaap:RelatedPartyTransactionsByRelatedParty
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency
us-gaap:AmountOfImpairmentToCarryingAmountOfRegulatoryAssets

us-gaap:AssetRetirementObligation

us-gaap:AssetRetirementObligationsNoncurrent
us-gaap:DisposalGroupClassification, us-gaap:PublicUtility, us-gaap:StatementBusinessSegments
us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperation
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:CapitalLeaseObligations

us-gaap:CapitalLeasedAssetsGross

us-gaap:CapitalizationLongtermDebtAndEquity

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:CommonStockValueOutstanding
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentCarryingAmount

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet
us-gaap:DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensation
us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent
us-gaap:AwardType
us-gaap:DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent

us-gaap:DeferredCostsAndOtherAssets

us-gaap:DeferredFinanceCostsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation

us-gaap:DeferredTaxLiabilitiesParentsBasisInDiscontinuedOperation

us-gaap:DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFairValueOfPlanAssets
us-gaap:RetirementPlanTaxStatus, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan
us-gaap:RetirementPlanType
fe:MedicareStatus, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
us-gaap:DefinedBenefitPlanByPlanAssetCategories
us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations

us-gaap:DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
dei:LegalEntity, fe:BusinessUnits, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:EquityMethodInvestmentOwnershipPercentage
us-gaap:ConsolidatedEntities, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:EquityMethodInvestments
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

us-gaap:FinanceLeaseLiability

us-gaap:FinanceLeaseLiabilityCurrent

us-gaap:FinanceLeaseLiabilityNoncurrent

us-gaap:FinanceLeaseLiabilityPaymentsDue

us-gaap:FinanceLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseRightOfUseAsset

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:GuaranteeObligationsCurrentCarryingValue
fe:OutstandingGuarantees
us-gaap:GuaranteedInsuranceContractTypeOfGuarantee

us-gaap:GuaranteeObligationsMaximumExposure
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsByNature, us-gaap:StatementBusinessSegments
us-gaap:GuaranteeObligationsByNature, us-gaap:SubsequentEventType
us-gaap:StatementBusinessSegments

us-gaap:InterestPayableCurrent
dei:LegalEntity, us-gaap:StatementGeographical
us-gaap:JointlyOwnedUtilityPlantProportionateOwnershipShare

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationNoncurrent
us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent

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

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LongtermPollutionControlBondCurrentAndNoncurrent

us-gaap:LongtermTransitionBondCurrentAndNoncurrent

us-gaap:NetRegulatoryAssets

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
fe:ExpirationPeriod, us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards
us-gaap:IncomeTaxAuthority
us-gaap:LongtermDebtType
us-gaap:OtherLongTermDebt

us-gaap:OtherLongTermInvestments

us-gaap:OtherReceivables
us-gaap:RetirementPlanType
us-gaap:PrescriptionDrugSubsidyReceiptsAfterYearFive

us-gaap:PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress
us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing
dei:LegalEntity, us-gaap:RegulatoryAgency
us-gaap:RegulatoryAssets
dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

us-gaap:RegulatoryAssetsNoncurrent

us-gaap:RegulatoryLiabilityNoncurrent
us-gaap:RegulatoryAsset

us-gaap:RemainingAmountsOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided
us-gaap:RegulatoryAsset

us-gaap:RestrictedCashCurrent
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
us-gaap:PlanName
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

us-gaap:ShortTermBorrowings

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

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
us-gaap:LongtermDebtType
us-gaap:UnsecuredDebt

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Income Tax Expense Benefit
Balance Sheet
Finite Lived Intangible Assets Net
Assets
Operating Lease Right Of Use Asset
Current Assets
Other Assets Current
NonCurrent Assets
Finite Lived Intangible Assets Net
PropertyPlantAndEquipmentNet
Accumulated Depreciation Depletion And Amortization Property Plant And Equipment
Liabilities
Operating Lease Liability
Current Liabilities
Operating Lease Liability Current
Noncurrent Liabilities
Operating Lease Liability Noncurrent
Stockholders Equity
Retained Earnings Accumulated Deficit
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Increase Decrease In Prepaid Deferred Expense And Other Assets
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Repayments Of Short Term Debt
Shares
Weighted Average Number Of Shares Outstanding Basic
OperatingLeaseLiability
Operating Lease Liability Current
NonoperatingIncomeExpense
Nonoperating Income Expense
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
FiniteLivedIntangibleAssets
Finite Lived Intangible Assets Net

Tables

  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
 us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock██████▇▇▆▆▃▃▁543.0543.0542.0542.0541.0540.0532.0531.0512.0512.0478.0477.0445.334111NANANA442.344218NANANA423.560397NANANA421.10257NANANA418.628559NANANA418.216437NANANA418.216437NANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding NA543.0543.0543.0NA542.0533.0533.0NA505.0479.0478.0NA446.0445.0444.0NA427.0425.0426.0NA424.0423.0423.0NA421.0421.0420.0NA419.0418.0419.0NA419.0419.0420.0NA420.0420.0
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic NA542.0542.0541.0NA538.0532.0530.0NA503.0477.0476.0NA444.0444.0443.0NA425.0425.0424.0NA423.0422.0421.0NA420.0420.0419.0NA418.0418.0418.0NA417.0417.0418.0NA418.0418.0
 us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities us-gaap:EmployeeStockOptionNA0.080.00.0NA0.00.00.0NA1.01.01.0NA1.01.01.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:EarningsPerShareBasic ▇▇▇▇▇▇▇▇▇▆▇█▄▇▇▇▁▇▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇0.449999999999999960.840.570.14-0.20.730.580.590.25-1.020.282.55-5.620.890.390.46-13.440.89-2.560.78-0.530.940.440.53-0.730.790.160.50.340.52-0.390.47-0.351.020.450.730.231.220.43
us-gaap:EarningsPerShareDiluted ▇▇▇▇▇▇▇▇▇▆▇█▄▇▇▇▁▇▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇0.449999999999999960.840.570.14-0.20.720.580.590.25-1.020.282.54-5.620.890.390.46-13.440.89-2.560.77-0.530.930.440.53-0.730.790.150.490.340.52-0.390.47-0.351.010.450.730.231.220.43
us-gaap:IncomeLossFromContinuingOperationsPerBasicShare ▇█▇▆▅███▇█▇▆▁█▇▇3.9000000000000013e-078.5e-075.699999999999999e-075.0000000000000004e-08-3.3e-077.2e-076.3e-076.6e-073.4000000000000003e-076.6e-072.2e-074e-08-2.39e-066.800000000000001e-074.9e-075.8e-07NANANANA-5.3e-079.399999999999999e-074.4e-075.3e-07-7.3e-077.900000000000001e-071.6e-072.9e-073.4000000000000003e-075e-07-4.0000000000000003e-074.6000000000000004e-07-3.6e-071.01e-064.4e-077.2e-07NANANA
us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare ▇█▇▆▅███▇█▇▆▁█▇▇3.9000000000000013e-078.5e-075.699999999999999e-075.0000000000000004e-08-3.3e-077.2e-076.3e-076.6e-073.4000000000000003e-076.6e-072.2e-074e-08-2.39e-066.800000000000001e-074.9e-075.8e-07NANANANA-5.3e-079.300000000000001e-074.4e-075.3e-07-7.3e-077.900000000000001e-071.5e-072.9e-073.4000000000000003e-075e-07-4.0000000000000003e-074.6000000000000004e-07-3.6e-071e-064.4e-077.2e-07NANANA
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
 Margin from Continuing Operations us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,fe:RegulatedDistributionNA2661.02188.02358.0NA2636.02192.02573.0NA2766.02352.02576.0NA2610.02262.02490.0NANANANANANANANANANANANANANANANANANANANANANANA
 Margin from Continuing Operations us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,fe:RegulatedTransmissionNA413.0384.0401.0NA375.0372.0356.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
 TTM Greenblatt ROC _ _████████████▆███▁█▇█▇███▇█▇███▇█▇███▇██394.0721.0515.0532.0615.0681.0585.0629.0512.0710.0687.0597.0-1830.0884.0544.0574.0-8924.0861.0-975.0776.0236.0908.0554.0594.0-337.0716.0292.0398.0401.0512.054.0654.0-34.0907.0557.0746.0-230.01022.0486.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest NA452.0307.056.0NA387.0307.0315.0NA-470.0286.01313.0NA384.0162.0206.0NA373.0-1077.0336.0NA370.0159.0206.0-292.0301.057.0195.0127.0194.0-202.0172.0-130.0403.0172.0285.042.0506.0256.0
us-gaap:CostsAndExpenses ▁▁▁▁▁▁▁▁▁▁▁▁▃▂▂▂█▂▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂2143.02301.02007.02177.02058.02282.01931.02254.02198.02354.02017.02379.05272.02830.02765.02978.012299.03056.04376.03093.03305.03215.02911.03303.03820.03172.03204.03791.03246.03524.03465.03075.03079.03404.03312.03332.04028.03697.03574.0
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ███▇▇███████▆███▁█▇█▇███▇█▇███▇█▇███▇██216.0576.0373.0-36.0-249.0496.0422.0448.0169.0520.0382.0429.0-2086.0635.0291.0331.0-9185.0631.0-1219.0541.0-396.0621.0302.0366.0-574.0485.090.0170.0208.0286.0-222.0312.0-253.0734.0315.0528.0123.0855.0307.0
us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest ▇█▇▆▅█▇█▇█▇▇▁▇▇▇212.0460.0307.024.0-181.0389.0341.0355.0182.0387.0267.0177.0-1061.0301.0219.0257.0NANANANA-226.0395.0187.0222.0-306.0333.064.0122.0142.0209.0-168.0192.0-153.0422.0184.0302.0NANANA
us-gaap:IncomeTaxExpenseBenefit ▇▇▇▇▇▇▇▇▇▇▇███▇▇▁█▇█▇█▇█▇█▇▇▇▇▇▇▇█▇█▇█▇4.0116.066.0-60.0-68.0107.081.093.0-13.0133.0115.0252.0413.0239.0117.0126.0-3389.0251.0-130.0213.0-170.0226.0115.0144.0-268.0152.026.048.066.077.0-58.0116.0-105.0309.0127.0222.024.0311.0101.0
us-gaap:InterestAndDebtExpense ▃▃▃▃▃▃▂▂▂▂█▂▄▅▄▄▄▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▂▁▃▂▂▃▃273.0266.0263.0263.0260.0261.0259.0253.0258.0255.0369.0250.0296.0305.0290.0287.0294.0286.0289.0288.0286.0285.0282.0279.0271.0275.0262.0265.0245.0257.0256.0256.0251.0230.0274.0246.0245.0267.0265.0
us-gaap:InterestExpense ▃▃▃▃▃▃▂▂▂▂█▂▄▅▄▄▄▄▄▄▄▄▄▃▃▃▃▃▂▂▂▂▂▁▃▂273.0266.0263.0263.0260.0261.0259.0253.0258.0255.0369.0250.0296.0305.0290.0287.0294.0286.0289.0288.0286.0285.0282.0279.0271.0275.0262.0265.0245.0257.0256.0256.0251.0230.0274.0246.0NANANA
us-gaap:NetIncomeLoss ▇▇▇▇▇▇▇▇▇▆▇█▄▇▇▇▁▇▆▇▆▇▇▇▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇242.0454.0309.074.0-111.0391.0312.0320.0138.0-458.0299.01369.0-2499.0396.0174.0205.0-5796.0380.0-1089.0328.0-226.0395.0187.0222.0-306.0333.064.0208.0142.0218.0-164.0196.0-148.0425.0187.0306.098.0511.0181.0
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic ▆▇▆▆▆▆▆▆▆▅▆█▁▆▆▆242.0454.0309.074.0-111.0391.0308.0315.0128.0-512.0134.01213.0-2499.0396.0174.0205.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted ▁█242.0454.0NANA-111.0391.0NANA128.0-512.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NonoperatingIncomeExpense ▅▅▅▃▁▅▅▅▄▅▄▅▄▅▅▅▄▅▅▅▂▄▅▅▅▅▅▅▅▅▄▄▅▅▅▅█▅▅-178.0-145.0-142.0-568.0-864.0-185.0-163.0-181.0-343.0-190.0-305.0-168.0-256.0-249.0-253.0-243.0-261.0-230.0-244.0-235.0-632.0-287.0-252.0-228.0-237.0-231.0-202.0-228.0-193.0-226.0-276.0-342.0-219.0-173.0-242.0-218.0353.0-202.0-214.0
us-gaap:OperatingIncomeLoss ████████████▆███▁█▇█▇███▇█▇███▇█▇███▇██394.0721.0515.0532.0615.0681.0585.0629.0512.0710.0687.0597.0-1830.0884.0544.0574.0-8924.0861.0-975.0776.0236.0908.0554.0594.0-337.0716.0292.0398.0401.0512.054.0654.0-34.0907.0557.0746.0-230.01022.0486.0
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▆▆▆▅▆▆▆▆▄▅▅▁▅▅▅▆▅▆▇▇▆▄▄▅█▃▆▅▅▄▃▄█▄▅▄-3.0-2.0-2.0-18.0-7.0-4.0-5.0-5.0-20.0-12.0-13.0-56.0-9.0-12.0-12.01.0-10.0-7.012.08.0-6.0-25.0-28.0-16.014.0-32.0-7.0-13.0-15.0-24.0-38.0-24.018.0-22.0-16.0-21.0NANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedDefinedBenefitPlansAdjustment▄▄▄▃▄▄▄▄▂▃▃▅▃▃▄▃▄▃▃▃▃▃▃▂█▂▂▂▄▁▁▂█▂▂▂-3.0-2.0-3.0-18.0-8.0-4.0-5.0-6.0-21.0-14.0-14.04.0-19.0-12.0-10.0-12.0-3.0-11.0-11.0-11.0-14.0-19.0-19.0-20.025.0-26.0-26.0-26.0-7.0-29.0-33.0-28.029.0-22.0-21.0-24.0NANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedGainLossNetCashFlowHedgeParent▁▁█▁█▁▁█0.00.01.00.01.00.00.01.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncomeNA-2.0-2.0-18.0NA-4.0-5.0-5.0NA-12.0-13.0-56.0NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense NA100.0103.0100.0NA57.080.054.0NA49.048.067.0NA19.011.014.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems us-gaap:CorporateNonSegmentNA13.07.025.0NA24.038.011.0NA19.0-1.016.0NA15.010.06.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems us-gaap:MaterialReconcilingItemsNA-1.0-2.0-6.0NA-7.0-8.0-7.0NA-8.0-10.0-9.0NA-13.0-13.0-7.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,fe:RegulatedDistributionNA81.090.075.0NA36.046.046.0NA34.056.056.0NA16.014.015.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,fe:RegulatedTransmissionNA7.08.06.0NA4.04.04.0NA4.03.04.0NA1.00.00.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▁▃▁▂▂▂▁▂▂▃▂▂▂▅▄▄▄▆▄▅▄▆▄▅▄▅▄▆▅▆▄▅▃▇▅▆▅█▆2596.02983.02493.02629.02673.02926.02448.02806.02710.02986.02629.02892.02681.03714.03309.03552.03375.03917.03401.03869.03541.04123.03465.03897.03483.03888.03496.04189.03633.04032.03507.03723.02995.04311.03869.03990.03792.04719.04060.0
us-gaap:Revenues ▁▃▁▂▁▂▁▂▂▃▁▂▂▅▄▄▄▅▄▅▄▆▄▅▄▅▄▆▅▆▄▅▃▇▅▆▅█▆2537.03022.02522.02709.02673.02963.02516.02883.02710.03064.02625.02862.02681.03714.03309.03552.03375.03917.03401.03869.03541.04123.03465.03897.03483.03888.03496.04189.03633.04032.03507.03723.02995.04311.03869.03990.03792.04719.04060.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:Assets ▄▃▃▃▃▂▂▂▂▁▁▁▃▃▃▃▃▇▇██████▇▇▇▇▇▇▇▇▆▆▅▅▅▅44464.042938.042403.042090.042301.041506.040884.040490.040063.039443.038971.038795.042257.043649.043327.043212.043148.051961.051401.052695.052187.052663.053005.052521.052166.051224.051388.051228.050424.050383.050157.050424.050406.048738.048048.047691.047326.046661.047596.0
us-gaap:LiabilitiesAndStockholdersEquity ▄▃▃▃▃▂▂▂▂▁▁▁▃▃▃▃▃▇▇██████▇▇▇▇▇▇▇▇▆▆▅▅▅▅44464.042938.042403.042090.042301.041506.040884.040490.040063.039443.038971.038795.042257.043649.043327.043212.043148.051961.051401.052695.052187.052663.053005.052521.052166.051224.051388.051228.050424.050383.050157.050424.050406.048738.048048.047691.047326.046661.047596.0
us-gaap:StockholdersEquity ▃▃▃▃▃▃▃▃▃▃▄▄▁▃▃▃▃▇▆▇▇▇▇▇▇▇▇▇▇▇▇████████7237.07188.07143.06814.06975.07272.07269.06932.06814.06873.07699.07375.03925.06406.06320.06139.06241.011503.011407.012463.012421.012627.012530.012348.012420.012702.012683.012602.012692.012544.012799.012996.013084.013433.013497.013323.013280.013046.012998.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:AssetsCurrent ▆▁▁▁▂▃▂▂▂▃▂▂▄▄▃▃▄▅▄▄▄▆▇▆▆▆▇█▆▅▅▅▆▆▅▅▅▅▇3714.02162.01986.02003.02444.02616.02386.02314.02392.02596.02363.02310.03108.02931.02755.02760.02950.03480.03076.03230.03040.03833.04113.04011.03876.03785.04183.04577.03887.03559.03560.03499.03768.03709.03608.03477.03355.03591.04118.0
us-gaap:CashAndCashEquivalentsAtCarryingValue █▂▁▁▃▄▂▁▂▃▂▂▃▂▁▁▂▃▂▁▁▁▁▁▁▁▁▁▂▂▁▁▁▁▁▁▂▂▃1734.0260.0116.0152.0627.0716.0422.0174.0367.0436.0256.0248.0589.0399.0114.0164.0199.0551.0199.0146.0131.086.094.090.085.0109.076.0109.0218.0222.071.067.0172.0150.094.074.0202.0291.0476.0
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents █▂▁▁▃▄▂▁▂▂▂▂▃▂▁▁▁1801.0296.0165.0185.0679.0750.0474.0210.0429.0487.0324.0299.0643.0435.0171.0208.0260.0NANANA213.0NANANANANANANANANANANANANANANANANANA
us-gaap:AccountsReceivableNetCurrent 1203.0NANANA1091.01130.01109.01263.01221.01317.01231.01279.01463.01370.01375.01396.01440.01470.01341.01432.01415.01592.01590.01675.01554.01605.01731.01869.01720.01579.01646.01631.01614.01604.01635.01449.01525.01633.01578.0
us-gaap:InventoryNet ▂▂▂▁▁▁▁▁▁▁▁▁▃▄▄▄▄▆▆▇▇▆▇▆▇▆▇▆▆▆▇▇▇▇██▇▇▇317.0308.0303.0285.0281.0258.0261.0268.0252.0240.0281.0273.0463.0543.0553.0531.0564.0699.0759.0781.0785.0738.0792.0762.0817.0771.0802.0740.0752.0731.0806.0835.0861.0875.0921.0927.0811.0822.0866.0
us-gaap:OtherAssetsCurrent NA218.0286.0279.0157.0239.0280.0314.0175.0236.0263.0254.0151.0143.0151.0147.0158.0156.0163.0155.0167.0171.0166.0157.0160.0173.0205.0199.0241.0262.0248.0214.0176.0190.0171.0182.0122.0189.0203.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:PropertyPlantAndEquipmentGross 43726.0NANANA41767.0NANANA39469.0NANANA39778.0NANANA43767.0NANANA49952.0NANANA47484.0NANANA44228.0NANANA43210.0NANA40587.040122.039350.039568.0
us-gaap:ConstructionInProgressGross ▃▄▃▃▂▂▂▂▂▂▂▁▁▂▂▃▂▇▇█▇▆▆█▇▆▆█▆▆▆▇▆▆▅▅▅▄▃1578.01651.01432.01456.01310.01370.01245.01199.01235.01290.01150.01120.01026.01355.01249.01588.01351.02394.02389.02694.02422.02327.02282.02633.02449.02301.02180.02661.02304.02301.02230.02361.02293.02119.01937.02065.02054.01720.01465.0
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ▃▃▃▃▂▂▂▂▂▁▁▁▃████▇▇▇▇▇▆▆▆▆▅▅▅▄▄▄▄▄▃▃▃▃▃11938.011971.011818.011635.011427.011234.011139.010961.010793.010468.010463.010267.011925.016086.015999.015769.015731.015450.015295.015421.015160.014917.014728.014508.014150.014040.013797.013555.013280.013167.013027.012823.012600.012434.012336.012086.011839.011803.011593.0
us-gaap:PropertyPlantAndEquipmentNet ▅▄▄▄▃▃▃▂▂▂▁▁▁▂▁▁▂████▇▇▇▆▆▅▅▅▅▄▅▄▃▃▃▂▂▂33294.032857.032408.032005.031650.031152.030678.030266.029911.029407.029021.028570.028879.029498.029179.028795.029387.037833.037461.037644.037214.036610.036416.036117.035783.034925.034516.033888.033252.033223.033091.033286.032903.031441.030768.030566.030337.029267.029942.0
us-gaap:LongTermInvestments ▁▃▃▃▃▃▃▃▃▃▃▃▇▇▇▇▇▇▇▆▆▇▇▇▇▇▇▇▇▇▇▇▇████▇▇605.01463.01457.01438.01451.01425.01403.01359.01299.01329.01313.01303.03184.03143.03095.03090.03026.03035.02983.02886.02788.03154.03234.03258.03222.03259.03260.03161.03104.03105.03100.03215.03194.03451.03518.03482.03522.03132.03156.0
us-gaap:Goodwill ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁████████████████████5618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.05618.06418.06418.06418.06418.06418.06418.06418.06418.06418.06418.06418.06447.06447.06447.06444.06444.06444.06441.06448.06456.0
us-gaap:FiniteLivedIntangibleAssetsNet 73.0NANANA80.0NANANA93.0NANANA105.0NANANA120.0NANANA331.0NANANA496.0NANANA588.0NANANA702.0NANANA803.0NANA
us-gaap:OperatingLeaseRightOfUseAsset 265.0NANANA231.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▅▃▃▄▄▂▃▃▃▁▂▂▄▃▃▄▅▄▅▅▆▅▆▆▇▅▆▆█████▇▇██▃▃1106.0713.0812.0935.01039.0618.0705.0831.0752.0413.0572.0592.01053.0742.0871.01028.01153.0907.01076.01238.01379.01218.01301.01345.01456.01169.01279.01386.01674.01698.01638.01665.01719.01580.01588.01716.01641.0751.0769.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:AccountsPayableCurrent ▁▂▂▂▂▂▁▂▂▃▂▃▃▂▂▂▃▂▂▃▃▃▃▄▅▄▆▇▅▃▂▃█▂▃▂▄▃▄827.0891.0882.0898.0918.0893.0810.0892.0965.0997.0909.01005.01027.0924.0932.0977.01043.0944.0938.01000.01075.0994.01034.01102.01279.01190.01341.01455.01250.0995.0950.0982.01599.0925.01052.0918.01174.01009.01122.0
us-gaap:AccruedIncomeTaxesCurrent █▇▆▆▆▆▃▆▆▅▅▅▆▅▅▆▇▆▃▅▅▅▄▅▅▄▂▅▄▂▁▂▆▅▃▃▆▄▂640.0601.0563.0566.0545.0537.0416.0562.0533.0529.0508.0530.0571.0520.0518.0555.0580.0537.0439.0513.0519.0508.0467.0503.0490.0489.0397.0527.0485.0401.0338.0392.0543.0508.0436.0442.0558.0482.0399.0
us-gaap:LiabilitiesCurrent ▄▂▁▂▄▃▃▃▄▅▄▄▃▃▄█▇▇▆▆▅▅▆▆▅▅▆███▇▇█▅▆▅▄▄▅5004.03077.02544.03697.04862.04239.03983.04324.04634.05800.05068.05065.04077.04255.04647.07657.07126.07043.06759.06389.05602.05876.06789.06262.05561.05979.06173.07737.07637.07955.07533.07132.07605.05920.06082.05773.04855.04863.05544.0
us-gaap:LongTermDebtCurrent 146.0NANANA380.0NANANA503.0NANANA1082.0NANANA1685.0NANANA1166.0NANANA804.0NANANA1415.0NANANA1999.0NANANA-1621.0NANA
us-gaap:OperatingLeaseLiabilityCurrent 42.0NANANA32.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherLiabilitiesCurrent ▂▂▁▂█▆▄▆▅▅▂▄▃▄▃▄▃▅▃▅▃▄▃▅▃▄▃▄▃▄▃▅▅▅▃▅▅▅▃560.0586.0367.0572.01425.01084.0840.01051.01026.01012.0557.0882.0722.0867.0619.0848.0660.0915.0687.0970.0694.0824.0605.0908.0693.0850.0612.0863.0621.0872.0599.0946.01038.0942.0617.01009.0900.0980.0691.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:LiabilitiesNoncurrent ▂▂▂▂▃▂▂▂▃▂▁▁▅▄▄▄▄████████▇▇▇▇▇▇▇▇▆▆▅▆▅▅10092.010470.010736.010758.010846.010573.010579.010420.010864.010162.09743.09615.013140.011899.011778.011654.011589.014883.014887.014964.014971.015066.015115.014779.015007.014010.014115.014082.014261.014590.014372.014478.014529.013742.013295.013052.013456.012559.012611.0
 us-gaap:LongTermDebt dei:LegalEntity,us-gaap:DebtInstrument,us-gaap:LongtermDebtType fe:GlobalHolding,fe:SeniorSecuredTermLoan,us-gaap:SeniorLoans108.0NANANA114.0NANANA190.0NANANA275.0NANANA300.0NANANA300.0NANANA350.0350.0350.0350.0350.0350.0350.0350.0NANANANANANANA
 us-gaap:LongTermDebt us-gaap:ConsolidatedEntities,us-gaap:StatementBusinessSegments srt:ParentCompany,fe:OtherBusinessOperations█▆▆▆▁▁▁▂▁8199.9999999999987850.07850.07900.07100.07100.07100.07200.07100.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument fe:PhaseInRecoveryBonds245.0NANANA268.0268.0280.0280.0292.0292.0304.0304.0315.0315.0327.0327.0339.0339.0350.0350.0362.0362.0374.0374.0386.0NANANA445.0NANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis us-gaap:CarryingReportedAmountFairValueDisclosure██▇▆▅▅▄▄▃▂▂▂█▇█▅▅▄▄▅▅▅▄▄▄▄▄▂▁22377.022389.022168.021297.020074.019880.019508.019088.018315.017796.017650.017949.022261.022218.022646.019921.019885.019745.019664.020217.020244.020118.019728.019775.019828.019757.019258.018034.017049.0NANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis us-gaap:EstimateOfFairValueFairValueDisclosure▇██▆▅▅▄▃▂▂▂▂▅▅▅▃▃▄▄▄▄▄▄▄▄▄▃▂▁25465.026161.026278.023576.022928.022910.021890.020691.019266.018761.018876.019487.023038.022994.023164.020029.019829.021465.021627.021821.021519.021525.021195.021911.021733.021363.020816.019321.017957.0NANANANANANANANANANA
us-gaap:LongTermDebtAndCapitalLeaseObligations ███▇▅▅▅▅▄▂▂▃▇▇▆▄▄▄▄▅▅▅▄▅▅▄▄▃▂▁▁▂▁▁▁▁▂▂▂22131.022203.021980.020821.019618.019422.019053.018814.017751.016608.016461.016740.021115.021089.020582.017762.018192.018532.018348.018878.019192.019093.018570.019130.019176.018531.018415.016804.015831.015291.015449.015814.015179.015627.015159.015527.015716.015823.016491.0
us-gaap:DeferredIncomeTaxLiabilitiesNet NA3036.02876.02774.02849.02900.0NANA2502.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ▅▅▅▅▄▂▂▂▄▃▃▃▇▇▇▆▆▇███▇▇▇▇▃▃▃▃▄▄▄▄▂▂▂▃▁▁3345.03342.03401.03455.03065.02403.02414.02417.02906.02742.02717.02717.03975.03814.03784.03756.03719.04080.04177.04135.04245.03861.03836.03817.03932.02754.02732.02713.02689.03104.03088.03070.03080.02271.02257.02240.02823.02045.02134.0
us-gaap:OtherLiabilitiesNoncurrent ▅▁▃▃▅▅▆▆▇▄▂▁▅▃▄▄▅▂▃▃▄▂▃▃▄▂▄▄▅▅▅▅▆▆▇▇▇██1637.01117.01321.01357.01667.01755.01909.01902.02057.01591.01165.01057.01718.01435.01584.01606.01704.01269.01419.01430.01555.01191.01373.01332.01590.01258.01494.01532.01778.01716.01703.01751.01836.01904.01980.02011.02072.02127.02208.0
us-gaap:OperatingLeaseLiabilityNoncurrent 263.0NANANA241.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo 49.0NANANA40.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree 46.0NANANA40.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour 38.0NANANA36.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive 36.0NANANA29.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive 147.0NANANA154.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:StockholdersEquity ▃▃▃▃▃▃▃▃▃▃▄▄▁▃▃▃▃▇▆▇▇▇▇▇▇▇▇▇▇▇▇████████7237.07188.07143.06814.06975.07272.07269.06932.06814.06873.07699.07375.03925.06406.06320.06139.06241.011503.011407.012463.012421.012627.012530.012348.012420.012702.012683.012602.012692.012544.012799.012996.013084.013433.013497.013323.013280.013046.012998.0
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest 7237.0NANANA6975.0NANA36.06814.061.073.086.03925.0151.0163.0175.06241.011503.011407.012464.012422.012628.012531.012350.012422.012704.012685.012605.012695.012547.012803.013000.013093.013449.013512.013339.013299.013015.012950.0
us-gaap:AdditionalPaidInCapitalCommonStock ▂▃▄▄▅▅▆▆▇▇██▂▂▃▃▄▂▂▂▂▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁10076.010266.010673.010651.010868.011047.011411.011381.011530.011708.011975.011937.010001.09974.010272.010253.010555.010012.09984.09963.09952.09926.09895.09871.09847.09836.09817.09793.09776.09755.09744.09739.09769.09758.09756.09754.09765.09782.09782.0
us-gaap:RetainedEarningsAccumulatedDeficit ▃▃▃▃▂▃▂▂▂▂▂▂▁▃▂▂▂▆▆▆▆▇▇▆▆▇▇▇▇▇▇▇▇▇▇▇▇██-2888.0-3130.0-3584.0-3893.0-3967.0-3856.0-4247.0-4559.0-4900.0-5017.0-4559.0-4858.0-6262.0-3763.0-4159.0-4333.0-4532.01264.01190.02279.02256.02482.02391.02205.02285.02592.02560.02496.02590.02448.02690.02854.02888.03266.03310.03122.03047.04658.04607.0
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▆▆▆▆▆▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇████████▁▁-5.0-2.00.02.020.027.031.036.041.061.073.086.0142.0151.0163.0175.0174.0184.0191.0179.0171.0177.0202.0230.0246.0232.0264.0271.0284.0299.0323.0361.0385.0367.0389.0405.0426.0-1436.0-1433.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:NetCashProvidedByUsedInOperatingActivities ▆▆▆▂▆▇▆▃▆▆▆▁▇█▆▆▆▇▆▆▇█▆▄572.0701.0710.0-560.0730.01112.0807.0-182.0852.0846.0592.0-880.01046.01280.0697.0785.0791.01120.0822.0638.01130.01327.0797.0193.0NANANANANANANANANANANA-413.0834.01198.0540.0
us-gaap:NetCashProvidedByUsedInInvestingActivities ▅▅▅▆▄▅▅▆▅▆█▁▇▆▅▅▄▅▃▄▄▆▃▅-737.0-765.0-747.0-659.0-792.0-745.0-706.0-630.0-781.0-672.0-422.0-1143.0-535.0-670.0-749.0-762.0-805.0-709.0-902.0-865.0-835.0-594.0-945.0-748.0NANANANANANANANANANANA-534.0-401.0-20.0-676.0
us-gaap:NetCashProvidedByUsedInFinancingActivities █▄▃▅▃▃▄▅▃▃▃█▂▂▃▃▂▃▄▄▂▁▄▅1670.0195.017.0725.0-9.0-91.0163.0593.0-129.0-11.0-145.01679.0-321.0-325.02.0-58.0-338.0-59.0133.0242.0-250.0-741.0152.0560.0NANANANANANANANANANANA819.0-522.0-1363.0-489.0
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect █▃▃▁▂▄▄▂▃▃1505.0131.0-20.0-494.0-71.0276.0264.0-219.0-58.0163.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:DepreciationDepletionAndAmortization ▅▃▄▄▂▅▅▅▅▅▄▄▆▆▅▅▇▇▆▆▆▇▆▆█▅▄▄▅█▅▅▁▅▅395.0202.0307.0295.0148.0367.0357.0345.0381.0399.0324.0280.0452.0456.0400.0392.0557.0518.0467.0455.0453.0514.0444.0425.0632.0343.0322.0266.0389.0628.0374.0352.019.0333.0347.0NANANANA
us-gaap:IncreaseDecreaseInInventories █▁9.05.0NANA23.0-15.017.012.019.0-15.08.0-36.00.0-4.021.0-11.04.0-46.05.0-4.047.0-32.030.0-30.046.0-31.062.0-12.021.0-75.0-16.0-26.0-13.0-46.0-9.0118.048.0-38.016.0
us-gaap:NetCashProvidedByUsedInOperatingActivities ▆▆▆▂▆▇▆▃▆▆▆▁▇█▆▆▆▇▆▆▇█▆▄572.0701.0710.0-560.0730.01112.0807.0-182.0852.0846.0592.0-880.01046.01280.0697.0785.0791.01120.0822.0638.01130.01327.0797.0193.0NANANANANANANANANANANA-413.0834.01198.0540.0
us-gaap:NetIncomeLoss ▇▇▇▇▇▇▇▇▇▆▇█▄▇▇▇▁▇▆▇▆▇▇▇▆▇▇▇▇▇▇▇▇▇▇▇▇▇▇242.0454.0309.074.0-111.0391.0312.0320.0138.0-458.0299.01369.0-2499.0396.0174.0205.0-5796.0380.0-1089.0328.0-226.0395.0187.0222.0-306.0333.064.0208.0142.0218.0-164.0196.0-148.0425.0187.0306.098.0511.0181.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:NetCashProvidedByUsedInInvestingActivities ▅▅▅▆▄▅▅▆▅▆█▁▇▆▅▅▄▅▃▄▄▆▃▅-737.0-765.0-747.0-659.0-792.0-745.0-706.0-630.0-781.0-672.0-422.0-1143.0-535.0-670.0-749.0-762.0-805.0-709.0-902.0-865.0-835.0-594.0-945.0-748.0NANANANANANANANANANANA-534.0-401.0-20.0-676.0
us-gaap:PaymentsToAcquireProductiveAssets ▄▄▄▃▅▄▄▃▅▄▅▃▅▃▄▃▄▄▆▄▄▃▆▄▆▄█▆▄▃▃▆█▅▁▃▅▂▃678.0687.0676.0616.0753.0684.0674.0554.0733.0635.0724.0583.0740.0593.0666.0588.0679.0664.0794.0698.0679.0539.0818.0668.0839.0664.0988.0821.0678.0548.0586.0826.0992.0775.0412.0589.0749.0512.0569.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
us-gaap:NetCashProvidedByUsedInFinancingActivities █▄▃▅▃▃▄▅▃▃▃█▂▂▃▃▂▃▄▄▂▁▄▅1670.0195.017.0725.0-9.0-91.0163.0593.0-129.0-11.0-145.01679.0-321.0-325.02.0-58.0-338.0-59.0133.0242.0-250.0-741.0152.0560.0NANANANANANANANANANANA819.0-522.0-1363.0-489.0
us-gaap:ProceedsFromIssuanceOfLongTermDebt ▁▂▄▅▁▁▂▄▃▁▂▁▂▂█▂▄▂▁▁▁▃▁▁▃▂▅▄▃▂▂▅▁▂▁▁▁▁▂0.0250.01175.02000.0200.0150.0550.01400.0850.0174.0450.00.0625.0550.03250.0250.01455.0521.00.00.0227.0884.0200.00.0750.0641.01670.01467.01000.0500.0445.01800.090.0478.0182.00.01.0100.0286.0
 us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:FairValueByMeasurementBasis us-gaap:CarryingReportedAmountFairValueDisclosure▁▂▅█▂▂0.0250.01175.02000.0200.0150.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:RepaymentsOfLongTermDebt ▁▁▂▅▁▁▂▄▃▁▅█▄▆▃▂▇▃▄▁▁▃▂▁▄▂▃▃▅▄▆▆▁▂▄▁▃▄▄4.028.0304.0778.05.027.0129.0628.0330.027.0775.01476.0580.0976.0524.0211.01314.0436.0550.031.098.0489.0244.048.0697.0137.0436.0489.0938.0694.01012.0956.070.0124.0730.016.0328.0579.0643.0
us-gaap:PaymentsOfDividendsCommonStock ▆▆▆▆▆▆▅▅▄▄▃▃▂▂▂▂▁▁▁▁▁▁▁▁▁▁▁▁███████████211.0212.0211.0211.0205.0206.0202.0201.0184.0184.0172.0171.0161.0159.0160.0159.0153.0153.0153.0152.0152.0152.0151.0152.0152.0150.0151.0151.0230.0230.0230.0230.0230.0230.0230.0230.0230.0231.0230.0
  2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStock


Common
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value543543542542541540532531512512478477445442423421418418418304304304304
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value543543543542533533505479478446445444427425426424423423421421420419418419419419420420420343305305306
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value542542541538532530503477476444444443425425424423422421420420419418418418417417418418418342304304304
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EmployeeStockOption


Antidilutive
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value0.080.00.00.00.00.01.01.01.01.01.01.0
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.450.840.570.14-0.20.730.580.590.25-1.020.282.55-5.620.890.390.46-13.440.89-2.560.78-0.530.940.440.53-0.730.790.160.50.340.52-0.390.47-0.351.020.450.730.231.220.430.150.610.590.870.51
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.450.840.570.14-0.20.720.580.590.25-1.020.282.54-5.620.890.390.46-13.440.89-2.560.77-0.530.930.440.53-0.730.790.150.490.340.52-0.390.47-0.351.010.450.730.231.220.430.150.610.590.870.51
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.390.850.570.05-0.330.720.630.660.340.660.220.04-2.390.680.490.58-0.530.940.440.53-0.730.790.160.290.340.5-0.40.46-0.361.010.440.72
Percentage of IncomeLossFromContinuingOperationsPerBasicShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Diluted Share

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.390.850.570.05-0.330.720.630.660.340.660.220.04-2.390.680.490.58-0.530.930.440.53-0.730.790.150.290.340.5-0.40.46-0.361.00.440.72
Percentage of IncomeLossFromContinuingOperationsPerDilutedShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value45230756387307315-470.02861313384162206373-1077.0336370159206-292.030157195127194-202.0172-130.04031722854250625666-29.0204276165
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax15.212.32.113.212.511.2-15.710.945.410.34.95.89.5-31.78.79.04.65.30.07.71.64.70.04.8-5.84.60.09.34.47.10.010.76.30.00.00.00.00.0

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value214323012007217720582282193122542198235420172379527228302765297812299305643763093330532152911330338203172320437913246352434653075307934043312333240283697357432612723331326132883
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.077.180.582.877.078.078.980.381.178.876.782.3196.676.283.683.8364.478.0128.779.993.378.084.084.80.081.691.690.50.087.498.882.60.079.085.683.50.078.388.00.00.00.00.00.0

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

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value216576373-36.0-249.0496422448169520382429-2086.0635291331-9185.0631-1219.0541-396.0621302366-574.048590170208286-222.0312-253.0734315528123855307
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.019.315.0-1.4-9.317.017.216.06.217.414.514.8-77.817.18.89.3-272.116.1-35.814.0-11.215.18.79.40.012.52.64.10.07.1-6.38.40.017.08.113.20.018.17.6

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value21246030724-181.0389341355182387267177-1061.0301219257-226.0395187222-306.033364122142209-168.0192-153.0422184302
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.015.412.30.9-6.813.313.912.76.713.010.26.1-39.68.16.67.2-6.49.65.45.70.08.61.82.90.05.2-4.85.20.09.84.87.6

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value-68.0-58.0-229.0-94.0-33.0-78.0-128.0-214.0-244.0-97.0-78.0-68.0
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest-14.8-18.9-954.2-24.2-9.7-22.0-33.1-80.1-137.9-32.2-35.6-26.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.3-2.3-8.7-3.2-1.3-2.8-4.3-8.1-8.4-2.6-2.4-1.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value413251136370258329416377322314205237
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest89.881.8566.795.175.792.7107.5141.2181.9104.393.692.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.810.15.212.610.511.713.914.311.18.56.26.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution15.811.76.014.312.213.215.616.613.00.00.00.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value115114117113116104
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest25.037.1487.529.034.029.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.94.64.53.94.73.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission28.230.029.530.531.629.5

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value4.011666-60.0-68.01078193-13.0133115252413239117126-3389.0251-130.0213-170.0226115144-268.015226486677-58.0116-105.03091272222431110178118119134111-185.012824854
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.03.92.6-2.3-2.53.73.33.3-0.54.54.48.715.46.43.53.5-100.46.4-3.85.5-4.85.53.33.70.03.90.71.10.01.9-1.73.10.07.23.35.60.06.62.50.00.00.00.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value-28.0-35.0-62.0-22.0-16.0-27.0-27.0-61.0127-33.0-27.0-29.0-11.0-26.0-13.0-39.0
Percentage of IncomeTaxExpenseBenefit-24.1-53.0103.3-20.6-19.8-29.0-20.3-53.050.4-13.8-23.1-23.0-4.420.0-6.1-17.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.9-1.4-2.4-0.8-0.7-1.0-0.9-2.34.4-0.9-0.8-0.8-0.3-0.8-0.3-0.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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

us-gaap:OperatingSegments, fe:RegulatedDistribution


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value10967-32.01036789126138931831211381678094137
Percentage of IncomeTaxExpenseBenefit94.0101.553.396.382.795.794.7120.036.976.6103.4109.566.5-61.544.160.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.72.7-1.23.52.73.24.25.23.24.93.73.94.32.42.43.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution4.23.1-1.44.03.23.64.76.13.80.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value35343426303134383249535245464741
Percentage of IncomeTaxExpenseBenefit30.251.5-56.724.337.033.325.633.012.720.545.341.317.9-35.422.118.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.21.41.30.91.21.11.11.41.11.31.61.51.11.41.21.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission8.68.98.67.08.28.810.011.310.00.00.00.00.00.00.00.0

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

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value-1.0-1.0-5.0-3.0-2.0-1.0-5.0-4.0-5.0-7.0-8.0-6.0
Percentage of IncomeTaxExpenseBenefit-0.9-1.58.3-2.8-2.5-1.1-3.8-3.5-2.0-2.9-6.8-4.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.0-0.2-0.1-0.1-0.0-0.2-0.2-0.2-0.2-0.2-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit0.00.00.00.00.00.00.00.00.00.00.00.0

Interest And Debt Expense

us-gaap:InterestAndDebtExpense

us-gaap:InterestAndDebtExpense


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value273266263263260261259253258255369250296305290287294286289288286285282279271275262265245257256256251230274246245267265231217208207213
Percentage of InterestAndDebtExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.08.910.510.09.78.910.69.09.58.514.08.611.08.28.88.18.77.38.57.48.16.98.17.20.07.17.56.30.06.47.36.90.05.37.16.20.05.76.50.00.00.00.00.0

us-gaap:InterestAndDebtExpense us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.0-1.00.00.00.0-1.0
Percentage of InterestAndDebtExpense0.0-0.40.00.00.0-0.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.00.00.00.0-0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OtherContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.0

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value273266263263260261259253258255369250296305290287294286289288286285282279271275262265245257256256251230274246
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.08.910.510.09.78.910.69.09.58.514.08.611.08.28.88.18.77.38.57.48.16.98.17.20.07.17.56.30.06.47.36.90.05.37.16.2

us-gaap:InterestExpense us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value888790959593932089290706556545148
Percentage of InterestExpense33.133.134.236.436.736.836.556.436.829.524.122.619.618.717.716.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.03.53.43.23.93.33.17.93.22.42.11.81.41.61.31.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MaterialReconcilingItems


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value-1.0-2.0-6.0-7.0-8.0-7.0-8.0-10.0-9.00.00.00.00.00.00.00.0
Percentage of InterestExpense-0.4-0.8-2.3-2.7-3.1-2.8-3.1-2.7-3.60.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.1-0.2-0.2-0.3-0.2-0.3-0.4-0.30.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MaterialReconcilingItems0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value124123127124124122127129128133134138139148150149
Percentage of InterestExpense46.646.848.347.547.948.249.835.051.243.646.248.148.651.252.152.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.24.94.84.25.14.34.34.94.43.64.03.93.54.43.93.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution4.85.75.64.85.94.94.75.75.20.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value55555249484543423938393943394040
Percentage of InterestExpense20.720.919.818.818.517.816.911.415.612.513.413.615.013.513.914.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.82.22.01.72.01.61.41.61.31.01.21.11.11.11.01.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission13.514.513.113.213.112.812.612.512.20.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value24245430974-111.0391312320138-458.02991369-2499.0396174205-5796.0380-1089.0328-226.0395187222-306.033364208142218-164.0196-148.04251873069851118150185179265155239234414119
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.015.212.42.8-4.213.412.711.45.1-15.311.447.3-93.210.75.35.8-171.79.7-32.08.5-6.49.65.45.70.08.61.85.00.05.4-4.75.30.09.94.87.70.010.84.50.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value-2.0-3.0-18.0-4.0-5.0-6.0-13.0-15.0-13.0-12.0-10.0-12.0
Percentage of NetIncomeLoss-0.4-1.0-24.3-1.0-1.6-1.92.8-5.0-0.9-3.0-5.7-5.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.1-0.7-0.1-0.2-0.2-0.4-0.6-0.4-0.3-0.3-0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.01.00.00.00.01.0
Percentage of NetIncomeLoss0.00.30.00.00.00.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value45430974391312320-458.02991369
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax15.212.42.813.412.711.4-15.311.447.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value24245430974-111.0391308315128-512.01341213-2499.0396174205
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.015.212.42.8-4.213.412.611.24.7-17.15.141.9-93.210.75.35.8

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted


Net
Period End2020-12-312020-09-302019-12-312019-09-302018-12-312018-09-30
Value242454-111.0391128-512.0
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.015.2-4.213.44.7-17.1

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-178.0-145.0-142.0-568.0-864.0-185.0-163.0-181.0-343.0-190.0-305.0-168.0-256.0-249.0-253.0-243.0-261.0-230.0-244.0-235.0-632.0-287.0-252.0-228.0-237.0-231.0-202.0-228.0-193.0-226.0-276.0-342.0-219.0-173.0-242.0-218.0353-202.0-214.0-192.0-150.0-121.0-136.0-156.0
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-4.9-5.7-21.6-32.3-6.3-6.7-6.5-12.7-6.4-11.6-5.8-9.5-6.7-7.6-6.8-7.7-5.9-7.2-6.1-17.8-7.0-7.3-5.90.0-5.9-5.8-5.40.0-5.6-7.9-9.20.0-4.0-6.3-5.50.0-4.3-5.30.00.00.00.00.0

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value394721515532615681585629512710687597-1830.0884544574-8924.0861-975.0776236908554594-337.071629239840151254654-34.0907557746-230.01022486315448415526416244487802346
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.024.220.720.223.023.323.922.418.923.826.120.6-68.323.816.416.2-264.422.0-28.720.16.722.016.015.20.018.48.49.50.012.71.517.60.021.014.418.70.021.712.00.00.00.00.00.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-3.0-2.0-2.0-18.0-7.0-4.0-5.0-5.0-20.0-12.0-13.0-56.0-9.0-12.0-12.01.0-10.0-7.0128.0-6.0-25.0-28.0-16.014-32.0-7.0-13.0-15.0-24.0-38.0-24.018-22.0-16.0-21.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.1-0.1-0.7-0.3-0.1-0.2-0.2-0.7-0.4-0.5-1.9-0.3-0.3-0.40.0-0.3-0.20.40.2-0.2-0.6-0.8-0.40.0-0.8-0.2-0.30.0-0.6-1.1-0.60.0-0.5-0.4-0.5

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-3.0-2.0-3.0-18.0-8.0-4.0-5.0-6.0-21.0-14.0-14.04.0-19.0-12.0-10.0-12.0-3.0-11.0-11.0-11.0-14.0-19.0-19.0-20.025-26.0-26.0-26.0-7.0-29.0-33.0-28.029-22.0-21.0-24.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0150.0100.0114.3100.0100.0120.0105.0116.7107.7-7.1211.1100.083.3-1200.030.0157.1-91.7-137.5233.376.067.9125.0178.681.2371.4200.046.7120.886.8116.7161.1100.0131.2114.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.1-0.1-0.7-0.3-0.1-0.2-0.2-0.8-0.5-0.50.1-0.7-0.3-0.3-0.3-0.1-0.3-0.3-0.3-0.4-0.5-0.5-0.50.0-0.7-0.7-0.60.0-0.7-0.9-0.80.0-0.5-0.5-0.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00.01.00.01.00.00.01.0
Percentage of OtherComprehensiveIncomeLossNetOfTax-0.0-0.0-50.0-0.0-14.3-0.0-0.0-20.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-2.0-2.0-18.0-4.0-5.0-5.0-12.0-13.0-56.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.1-0.7-0.1-0.2-0.2-0.4-0.5-1.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value100103100578054494867191114
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.44.13.81.93.31.91.61.82.30.50.30.4

us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value137.02524381119-1.0161510.06.0
Percentage of OtherNonoperatingIncomeExpense13.06.825.042.147.520.438.8-2.123.978.990.942.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.40.31.00.81.60.40.6-0.00.60.40.30.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MaterialReconcilingItems


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value-1.0-2.0-6.0-7.0-8.0-7.0-8.0-10.0-9.0-13.0-13.0-7.0
Percentage of OtherNonoperatingIncomeExpense-1.0-1.9-6.0-12.3-10.0-13.0-16.3-20.8-13.4-68.4-118.2-50.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.0-0.1-0.2-0.2-0.3-0.2-0.3-0.4-0.3-0.4-0.4-0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MaterialReconcilingItems0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherNonoperatingIncomeExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value819075364646345656161415
Percentage of OtherNonoperatingIncomeExpense81.087.475.063.257.585.269.4116.783.684.2127.3107.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.73.62.91.21.91.61.12.11.90.40.40.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution3.14.23.31.42.21.91.32.52.30.00.00.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value7.08.06.04.04.04.04.03.04.01.00.00.0
Percentage of OtherNonoperatingIncomeExpense7.07.86.07.05.07.48.26.26.05.30.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.30.20.10.20.10.10.10.10.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission1.72.11.51.11.11.11.20.91.30.00.00.0

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value259629832493262926732926244828062710298626292892268137143309355233753917340138693541412334653897348338883496418936334032350737232995431138693990379247194060
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-35.0-35.0-35.0-33.0-32.0-30.0-29.0-30.02794
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.2-1.4-1.3-1.1-1.3-1.1-1.1-1.01.03.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.2-1.4-1.3-1.1-1.3-1.1-1.1-1.01.03.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:ProductOrService

us-gaap:IntersegmentElimination, fe:DistributionServices


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-22.0-22.0-21.0-21.0-21.0-21.0-23.0-22.0-47.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.7-0.9-0.8-0.7-0.9-0.7-0.8-0.7-1.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.7-0.9-0.8-0.7-0.9-0.7-0.8-0.7-1.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination fe:DistributionServices100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IntersegmentElimination, fe:RetailGeneration


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-16.0-15.0-15.0-14.0-14.0-14.0-12.0-14.0-14.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.5-0.6-0.6-0.5-0.6-0.5-0.4-0.5-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.5-0.6-0.6-0.5-0.6-0.5-0.4-0.5-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination fe:RetailGeneration100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IntersegmentElimination, fe:WholesaleSales


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value3.02.01.02.03.04.06.06.05.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.10.10.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.10.10.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination fe:WholesaleSales100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:OperatingSegments, fe:DistributionServices, fe:RegulatedDistribution


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value12591503124112561230145711601286121014401228
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax48.550.449.847.846.049.847.445.844.648.246.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax48.550.449.847.846.049.847.445.844.648.246.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:DistributionServices fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:OtherServices, fe:RegulatedDistribution


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value3835313637423734314335
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.21.21.41.41.41.51.21.11.41.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.21.21.41.41.41.51.21.11.41.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:OtherServices fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:RetailGeneration, fe:RegulatedDistribution


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value842100582690487498980610589551059882
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax32.433.733.134.432.733.832.937.735.235.533.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax32.433.733.134.432.733.832.937.735.235.533.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RetailGeneration fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:TransmissionServices, fe:RegulatedTransmission


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value428408380397420371367352339341336
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:TransmissionServices fe:RegulatedTransmission100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:WholesaleSales, fe:RegulatedDistribution


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value6367507195100110106125133121
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.42.22.02.73.63.44.53.84.64.54.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.42.22.02.73.63.44.53.84.64.54.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:WholesaleSales fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value220226102148226722362588211324842321267522662479
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax84.887.586.286.283.788.486.388.585.689.686.285.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax84.887.586.286.283.788.486.388.585.689.686.285.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value428408380397420371367352339341336319
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.811.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.811.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService

fe:DistributionServices


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value12361481121912351210143611391265118714181181
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax47.649.648.947.045.349.146.545.143.847.544.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax47.649.648.947.045.349.146.545.143.847.544.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:DistributionServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:OtherServices


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value3835313638423735314338
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.21.21.41.41.41.51.21.11.41.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.51.21.21.41.41.41.51.21.11.41.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:OtherServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:RetailGeneration


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value82898981188985997579210449431045868
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax31.933.232.533.832.133.332.437.234.835.033.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax31.933.232.533.832.133.332.437.234.835.033.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:RetailGeneration100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:TransmissionServices


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value428408380397420371367352339341336
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:TransmissionServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:WholesaleSales


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value6670527298102113110131139126
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.52.32.12.73.73.54.63.94.84.74.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.52.32.12.73.73.54.63.94.84.74.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:WholesaleSales100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value253730222522270926732963251628832710306426252862268137143309355233753917340138693541412334653897348338883496418936334032350737232995431138693990379247194060
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax97.7101.3101.2103.0100.0101.3102.8102.7100.0102.699.899.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value-209.03.02.01.0-199.02.03.05.0-223.06.011110.00.00.00.00.00.00.0
Percentage of Revenues-8.20.10.10.0-7.40.10.10.2-8.20.20.40.40.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-8.10.10.10.0-7.40.10.10.2-8.20.20.40.40.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-31
Value-52.0-50.0-50.0-48.0-48.0-46.0-42.0-48.0-68.0-37.0-93.0-86.0-117.0-117.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues-1.7-2.0-1.8-1.6-1.9-1.6-1.5-1.6-2.6-1.3-2.5-2.6-3.3-3.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.7-2.0-1.9-1.6-2.0-1.6-1.5-1.6-2.6-1.3-2.5-2.6-3.3-3.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination148.6142.9142.9145.5150.0153.3144.8160.0-251.9-39.40.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MaterialReconcilingItems


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value-55.0-52.0-51.0-50.0-51.0-51.0-54.0-79.0-48.0-34.0-58.0-65.0-68.0-71.0-79.0-76.0
Percentage of Revenues-1.8-2.1-1.9-1.7-2.0-1.8-1.8-3.0-1.7-0.9-1.8-1.8-1.7-2.1-2.0-1.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.8-2.1-1.9-1.7-2.1-1.8-1.8-3.0-1.7-0.9-1.8-1.8-1.7-2.1-2.0-1.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MaterialReconcilingItems0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:ConsolidationItems, us-gaap:MajorCustomers

us-gaap:CorporateNonSegment, fe:ExternalCustomers


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value3.02.01.02.03.05.06.04.05.0
Percentage of Revenues0.10.10.00.10.10.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.10.10.00.10.10.20.20.20.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CorporateNonSegment fe:ExternalCustomers0.00.00.00.00.00.00.00.00.0

us-gaap:MaterialReconcilingItems, fe:InternalCustomers


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-55.0-52.0-51.0-50.0-51.0-51.0-54.0-79.0-48.0
Percentage of Revenues-1.8-2.1-1.9-1.7-2.0-1.8-1.8-3.0-1.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.8-2.1-1.9-1.7-2.1-1.8-1.8-3.0-1.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MaterialReconcilingItems fe:InternalCustomers0.00.00.00.00.00.00.00.00.0

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

us-gaap:OperatingSegments, fe:ExternalCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value261121402311259021452526271722852538
Percentage of Revenues86.484.985.387.485.387.688.787.088.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax87.585.887.988.587.690.091.086.987.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:ExternalCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:ExternalCustomers, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value408380397371368352341336319
Percentage of Revenues13.515.114.712.514.612.211.112.811.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.715.215.112.715.012.511.412.811.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:ExternalCustomers fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:InternalCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value504847464747496738
Percentage of Revenues1.71.91.71.61.91.61.62.61.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.71.91.81.61.91.71.62.51.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:InternalCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:InternalCustomers, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value5.04.04.04.04.04.05.05.04.0
Percentage of Revenues0.20.20.10.10.20.10.20.20.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.20.20.10.20.10.20.20.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:InternalCustomers fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:ConsolidationItems, us-gaap:ProductOrService

us-gaap:IntersegmentElimination, us-gaap:ProductAndServiceOther


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value-17.0-15.0-15.0-15.0
Percentage of Revenues-0.6-0.6-0.6-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.6-0.6-0.6-0.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:IntersegmentElimination us-gaap:ProductAndServiceOther0.00.00.00.0

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

us-gaap:OperatingSegments, fe:AlternativeRevenueProgram, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value25156825
Percentage of Revenues0.80.62.50.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.62.60.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:AlternativeRevenueProgram fe:RegulatedDistribution0.00.00.00.0

us-gaap:OperatingSegments, us-gaap:ProductAndServiceOther, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value26252323
Percentage of Revenues0.91.00.80.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.91.00.90.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments us-gaap:ProductAndServiceOther fe:RegulatedDistribution0.00.00.00.0

us-gaap:OperatingSegments, us-gaap:ProductAndServiceOther, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value5.04.04.04.0
Percentage of Revenues0.20.20.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.20.20.20.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments us-gaap:ProductAndServiceOther fe:RegulatedTransmission0.00.00.00.0

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

us-gaap:OperatingSegments, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302014-03-312013-03-31
Value215626612188235822972636219225732409276623522576261022622490270221892510262425522212
Percentage of Revenues85.088.186.887.085.989.087.189.288.990.389.690.070.368.470.169.064.464.963.660.959.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax83.189.287.889.785.990.189.591.788.992.689.589.170.368.470.169.064.464.963.660.959.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedDistribution97.9102.0101.9104.0102.7101.9103.7103.6103.8103.4103.8103.90.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302014-03-312013-03-31
Value432413384401423375372356343346341323342327313285275286248187176
Percentage of Revenues17.013.715.214.815.812.714.812.312.711.313.011.39.29.98.87.38.17.46.04.54.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.613.815.415.315.812.815.212.712.711.613.011.29.29.98.87.38.17.46.04.54.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:OperatingSegments fe:RegulatedTransmission100.9101.2101.1101.0100.7101.1101.4101.1101.2101.5101.5101.30.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:MajorCustomers

fe:ExternalCustomers


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value253730222522270926732963251628832710306426252862
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax97.7101.3101.2103.0100.0101.3102.8102.7100.0102.699.899.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:ExternalCustomers0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:MajorCustomers, us-gaap:ProductOrService

fe:OtherNonCustomerRevenue, fe:DerivativeRevenue


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.08.06.01.02.03.02.00.04.04.010.0
Percentage of Revenues0.00.30.20.00.10.10.10.00.10.20.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.30.20.00.10.10.10.00.10.20.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:OtherNonCustomerRevenue fe:DerivativeRevenue0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments

fe:Atsi, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value206202192204212184184174172167167158
Percentage of Revenues8.16.77.67.57.96.27.36.06.35.56.45.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax7.96.87.77.87.96.37.56.26.35.66.45.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:Atsi fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.00.00.00.0

fe:CommercialCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value589507544600572587628570580
Percentage of Revenues19.520.120.120.222.720.420.521.720.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax19.720.320.720.523.420.921.021.720.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:CommercialCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

fe:IndustrialCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value278259277286251249276262254
Percentage of Revenues9.210.310.29.710.08.69.010.08.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.310.410.59.810.38.99.210.08.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:IndustrialCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

fe:JcpAndL, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302019-12-312019-09-30
Value56434040
Percentage of Revenues2.21.41.51.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.21.41.51.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:JcpAndL fe:RegulatedTransmission0.00.00.00.0

fe:MidAtlanticInterstateTransmissionLLC, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value676858576758504944433430
Percentage of Revenues2.62.32.32.12.52.02.01.71.61.41.31.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.62.32.32.22.52.02.01.71.61.41.31.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:MidAtlanticInterstateTransmissionLLC fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.00.00.00.0

fe:OtherCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value202120222024232324
Percentage of Revenues0.70.80.70.70.80.80.80.90.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.70.80.80.80.80.90.80.90.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:OtherCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

fe:OtherCustomers, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value343472737174747169717271
Percentage of Revenues1.31.12.92.72.72.52.92.52.52.32.72.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.31.12.92.82.72.53.02.52.52.42.72.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:OtherCustomers fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.00.00.00.0

fe:ResidentialCustomers, fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value162112801319153811231484157212551463
Percentage of Revenues53.650.848.751.944.651.551.347.851.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax54.351.350.252.645.952.952.647.750.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:ResidentialCustomers fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.0

fe:Trail, fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value656158637055595854606360
Percentage of Revenues2.62.02.32.32.61.92.32.02.02.02.42.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2.52.02.32.42.61.92.42.12.02.02.42.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:Trail fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Revenues us-gaap:ProductOrService

fe:AlternativeRevenueProgram


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value25156825
Percentage of Revenues0.80.62.50.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.80.62.60.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:AlternativeRevenueProgram0.00.00.00.0

fe:ElectricWorldwideUnregulatedRevenue


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value144112188181218222260240248239
Percentage of Revenues4.84.46.96.18.77.78.59.18.76.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.84.57.26.28.97.98.79.18.66.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:ElectricWorldwideUnregulatedRevenue0.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricTransmission


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value408380397371367352339341336319339337
Percentage of Revenues13.515.114.712.514.612.212.511.112.811.112.69.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.715.215.112.715.012.512.511.412.811.012.69.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ElectricTransmission0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricityUsRegulated


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value2470203021242411193123092463204922952334
Percentage of Revenues81.780.578.481.476.780.180.478.180.262.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax82.881.480.882.478.982.382.577.979.462.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ElectricityUsRegulated0.00.00.00.00.00.00.00.00.00.0

us-gaap:ProductAndServiceOther


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-30
Value14141212
Percentage of Revenues0.50.60.40.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.50.60.50.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther0.00.00.00.0

us-gaap:Revenues us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value250820672160244619662344249921102321220025212200262422392562213023572065255221362337203822122190243820952354224328652409
Percentage of Revenues83.082.079.782.678.181.381.680.481.164.765.262.163.664.665.761.260.659.160.958.858.058.159.473.156.654.159.059.260.759.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax84.182.982.283.680.383.583.780.380.364.765.262.163.664.665.761.260.659.160.958.858.058.159.473.156.654.159.059.260.759.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:RegulatedDistribution0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

fe:RegulatedTransmission


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value428408380397420371367352339341336319264275256248269238199197191187187189179176178187184186184181182
Percentage of Revenues16.913.515.114.715.712.514.612.212.511.112.811.17.87.17.26.07.86.15.75.15.54.55.14.75.14.75.94.34.84.74.93.84.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax16.513.715.215.115.712.715.012.512.511.412.811.07.87.17.26.07.86.15.75.15.54.55.14.75.14.75.94.34.84.74.93.84.5
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax fe:RegulatedTransmission0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value44464429384240342090423014150640884404904006339443389713879542257436494332743212431485196151401526955218752663530055252152166512245138851228504245038350157504245040648738480484769147326466614759647866348053470834466340783430433521
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities

us-gaap:CorporateNonSegment


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1017101596910071061
Percentage of Assets2.32.42.42.42.5
Percentage of Assets2.32.42.42.42.5
Percentage of Assets us-gaap:CorporateNonSegment100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value3085529642286902773027702
Percentage of Assets69.470.171.665.664.2
Percentage of Assets69.470.171.665.664.2
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedDistribution100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value12592116111040495258755
Percentage of Assets28.327.426.022.520.3
Percentage of Assets28.327.426.022.520.3
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedTransmission100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Assetsus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value611626695101579057458896989610501255613638637486175531830
Percentage of Assets1.41.51.72.41.91.41.52.42.32.73.21.41.51.50.90.31.01.6
Percentage of Assets1.41.51.72.41.91.41.52.42.32.73.21.41.51.50.90.31.01.6
Percentage of Assets us-gaap:CorporateNonSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Assetsus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value302492986329642296422942829240289922869028530280882750427866276602782628276274482744727883
Percentage of Assets70.470.470.470.170.971.571.671.672.372.170.963.863.864.454.453.452.152.9
Percentage of Assets70.470.470.470.170.971.571.671.672.372.170.963.863.864.454.453.452.152.9
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedDistribution100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Assetsus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value120781191411753116111125511070109101040410017983396819356914289388034831481396988
Percentage of Assets28.128.127.927.427.127.126.926.025.425.225.021.421.120.715.516.215.413.3
Percentage of Assets28.128.127.927.427.127.126.926.025.425.225.021.421.120.715.516.215.413.3
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedTransmission100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value444644293842403420904230141506408844049040063394433897138795422574364943327432124314851961514015269552187526635300552521521665122451388512285042450383501575042450406487384804847691473264666147596478663480534304
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value72377188714368146975727272696932681468737699737539256406632061396241115031140712463124211262712530123481242012702126831260212692125441279912996130841343313497133231328013046129981272985458559
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets16.316.716.816.216.517.517.817.117.017.419.819.09.314.714.614.214.522.122.223.723.824.023.623.523.824.824.724.625.224.925.525.826.027.628.127.928.128.027.326.624.625.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-312015-12-312014-12-31
Value3.06.08.0112937414652738797150186258
Percentage of StockholdersEquity0.00.10.10.20.40.50.60.70.81.11.12.52.41.52.1
Percentage of Assets0.00.00.00.00.10.10.10.10.10.20.20.20.30.40.5
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312016-12-31
Value-8.0-8.0-8.0-9.0-9.0-10.0-10.0-10.0-11.0-22.0-28.0
Percentage of StockholdersEquity-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.2-0.6-0.4
Percentage of Assets-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-5.0-2.00.02.02027313641617386142174171246284385426-1539.0-1415.0-1380.0-50.0
Percentage of StockholdersEquity-0.1-0.00.00.00.30.40.40.50.60.90.91.23.62.81.42.02.22.93.2-18.0-16.50.00.0
Percentage of Assets-0.0-0.00.00.00.00.10.10.10.10.20.20.20.30.40.30.50.60.80.9-4.4-4.1-4.10.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value1007610266106731065110868110471141111381115301170811975119371000110555995298479776976997655444544854735509
Percentage of StockholdersEquity139.2142.8149.4156.3155.8151.9157.0164.2169.2170.3155.5161.9254.8169.180.179.377.074.773.563.763.70.00.0
Percentage of Assets22.723.925.225.325.726.627.928.128.829.730.730.823.724.519.118.919.419.420.615.615.916.30.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value5454545454545353515148484444424242424231313131
Percentage of StockholdersEquity0.70.80.80.80.80.70.70.80.70.70.60.71.10.70.30.30.30.30.30.40.40.00.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-2888.0-3130.0-3584.0-3893.0-3967.0-3856.0-4247.0-4559.0-4879.0-5017.0-4559.0-4858.0-6262.0-4532.0225622852590288830474609449541593487
Percentage of StockholdersEquity-39.9-43.5-50.2-57.1-56.9-53.0-58.4-65.8-71.6-73.0-59.2-65.9-159.5-72.618.218.420.422.122.953.952.50.00.0
Percentage of Assets-6.5-7.3-8.5-9.2-9.4-9.3-10.4-11.3-12.2-12.7-11.7-12.5-14.8-10.54.34.45.15.76.413.213.112.40.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value371421621986200324442616238623142392259623632310310829312755276029503480307632303040383341134011387637854183457738873559356034993768370936083477335535914118464636983320
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets8.45.04.74.85.86.35.85.76.06.66.16.07.46.76.46.46.86.76.06.15.87.37.87.67.47.48.18.97.77.17.16.97.57.67.57.37.17.78.79.710.69.7

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value173426011615262771642217436743625624858939911416419955119914613186949085109761092182227167172150947420229147611011019632281310874545129
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.90.60.30.41.51.71.00.40.91.10.70.61.40.90.30.40.51.10.40.30.30.20.20.20.20.20.10.20.40.40.10.10.30.30.20.20.40.61.02.32.91.80.80.92.51.60.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value1801296165185679750474210429487324299643435171208260213
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.10.70.40.41.61.81.20.51.11.20.80.81.51.00.40.50.60.4

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value120310911130110912631221131712311279146313701375139614401470134114321415159215901675155416051731186917201579164616311614160416351449152516331578163613921244
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.72.62.72.73.13.03.33.23.33.53.13.23.23.32.82.62.72.73.03.03.23.03.13.43.63.43.13.33.23.23.33.43.03.23.53.33.44.03.6

us-gaap:AccountsReceivableNetCurrent us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

fe:Customer


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-31
Value12031112102010091091
Percentage of AccountsReceivableNetCurrent100.00.00.00.0100.0
Percentage of Assets2.72.62.42.42.6
Percentage of Assets fe:Customer0.00.00.00.00.0

us-gaap:AccountsReceivableNetCurrent us-gaap:AccountsNotesLoansAndFinancingReceivablesByBillingStatusType

us-gaap:BilledRevenues


Accounts
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value6365646868608338369141010893800752725
Percentage of AccountsReceivableNetCurrent52.951.756.258.857.859.158.858.755.352.554.058.3
Percentage of Assets1.41.31.72.01.91.61.82.01.81.72.22.1
Percentage of Assets us-gaap:BilledRevenues0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:UnbilledRevenues


Accounts
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value567527535603607579640710721725640519
Percentage of AccountsReceivableNetCurrent47.148.343.841.242.240.941.241.344.747.546.041.7
Percentage of Assets1.31.21.31.41.41.11.21.41.41.51.81.5
Percentage of Assets us-gaap:UnbilledRevenues0.00.00.00.00.00.00.00.00.00.00.00.0

Inventory Net

us-gaap:InventoryNet

us-gaap:InventoryNet


Inventory
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value317308303285281258261268252240281273463543553531564699759781785738792762817771802740752731806835861875921927811822866852638647
Percentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.70.70.70.70.70.60.60.70.60.60.70.71.11.21.31.21.31.31.51.51.51.41.51.51.61.51.61.41.51.51.61.71.71.81.91.91.71.81.81.81.81.9

Other Assets Current

us-gaap:OtherAssetsCurrent

us-gaap:OtherAssetsCurrent


Other
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value218286279157239280314175236263254151143151147158156163155167171166157160173205199241262248214176190171182122189203210274154
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 Assets0.50.70.70.40.60.70.80.40.60.70.70.40.30.30.30.40.30.30.30.30.30.30.30.30.30.40.40.50.50.50.40.30.40.40.40.30.40.40.40.80.4

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value43726417673946939778437674995247484442284321040587401223935039568381682945127826
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets98.398.798.594.1101.495.791.087.785.785.184.884.383.179.784.681.1

us-gaap:PropertyPlantAndEquipmentGross us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value297752873527520259502497924553239732309821473
Percentage of PropertyPlantAndEquipmentGross68.168.869.765.257.149.250.552.249.7
Percentage of Assets67.067.968.761.457.947.046.045.842.6
Percentage of Assets fe:RegulatedDistribution0.00.00.093.690.288.184.983.479.1

fe:RegulatedTransmission


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value1291212023110411010293427703663455645078
Percentage of PropertyPlantAndEquipmentGross29.528.828.025.421.315.414.012.611.8
Percentage of Assets29.028.427.623.921.714.812.711.010.1
Percentage of Assets fe:RegulatedTransmission0.00.00.0106.1106.7103.5104.4106.0106.3

us-gaap:CorporateAndOther


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value10391009908824766482435360321
Percentage of PropertyPlantAndEquipmentGross2.42.42.32.11.81.00.90.80.7
Percentage of Assets2.32.42.31.91.80.90.80.70.6
Percentage of Assets us-gaap:CorporateAndOther0.00.00.00.00.00.00.00.00.0

Construction In Progress Gross

us-gaap:ConstructionInProgressGross

us-gaap:ConstructionInProgressGross


Construction
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value157816511432145613101370124511991235129011501120102613551249158813512394238926942422232722822633244923012180266123042301223023612293211919372065205417201465232215172735
Percentage of ConstructionInProgressGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.53.83.43.53.13.33.03.03.13.33.02.92.43.12.93.73.14.64.65.14.64.44.35.04.74.54.25.24.64.64.44.74.54.34.04.34.33.73.14.94.48.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value119381197111818116351142711234111391096110793104681046310267119251608615999157691573115450152951542115160149171472814508141501404013797135551328013167130271282312600124341233612086118391180311593113451118011397
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets26.827.927.927.627.027.127.227.126.926.526.826.528.236.936.936.536.529.729.829.329.028.327.827.627.127.426.826.526.326.126.025.425.025.525.725.325.025.324.423.732.133.2

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value332943285732408320053165031152306783026629911294072902128570288792949829179287952938737833374613764437214366103641636117357833492534516338883325233223330913328632903314413076830566303372926729942296351978819164
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets74.976.576.476.074.875.175.074.774.774.674.573.668.367.667.366.668.172.872.971.471.369.568.768.868.668.267.266.265.965.966.066.065.364.564.064.164.162.762.961.956.955.9

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

fe:AlleghenyGeneratingCompany, stpr:VA


Property
Period End2020-12-312019-12-312018-12-312017-12-31
Value157161188531
Percentage of PropertyPlantAndEquipmentNet0.50.50.61.8
Percentage of Assets0.40.40.51.3
Percentage of Assets fe:AlleghenyGeneratingCompany stpr:VA0.00.00.00.0

Long Term Investments

us-gaap:LongTermInvestments

us-gaap:LongTermInvestments


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value60514631457143814511425140313591299132913131303318431433095309030263035298328862788315432343258322232593260316131043105310032153194345135183482352231323156308130023023
Percentage of LongTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.43.43.43.43.43.43.43.43.23.43.43.47.57.27.17.27.05.85.85.55.36.06.16.26.26.46.36.26.26.26.26.46.37.17.37.37.46.76.66.48.68.8

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312011-02-252010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value56185618561856185618561856185618561856185618561856185618561856185618561856186418641864186418641864186418641864186418641864476447644764446444644464416448645665279525575557555755575557555755607
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets12.613.113.213.313.313.513.713.914.014.214.414.513.312.913.013.013.010.810.912.212.312.212.112.212.312.512.512.512.712.712.912.812.813.213.413.513.613.813.613.60.016.016.116.216.416.316.60.0

us-gaap:Goodwill us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Goodwillus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value500450045004500450045004500450045004500450045004500450045092500450045092
Percentage of Goodwill89.189.189.189.189.189.189.189.189.189.189.189.189.189.190.689.178.079.3
Percentage of Assets11.711.811.911.812.112.212.412.512.712.812.911.511.511.69.89.79.59.7
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedDistribution16.516.816.916.917.017.117.317.417.517.818.218.018.118.018.018.218.218.3

us-gaap:OperatingSegments, fe:RegulatedTransmission


Goodwillus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value614614614614614614614614614614614614614614526614614526
Percentage of Goodwill10.910.910.910.910.910.910.910.910.910.910.910.910.910.99.410.99.68.2
Percentage of Assets1.41.41.51.51.51.51.51.51.61.61.61.41.41.41.01.21.21.0
Percentage of Assets us-gaap:OperatingSegments fe:RegulatedTransmission5.15.25.25.35.55.55.65.96.16.26.36.66.76.96.57.47.57.5

us-gaap:Goodwill us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Goodwillus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302009-12-31
Value50045004500450045004509250925092509250925092509250925092509250925092502550255025502550255025555155515551555155515551555155515551
Percentage of Goodwill89.189.189.189.189.190.690.679.379.379.379.379.379.379.379.379.379.378.377.977.977.978.078.086.186.286.186.085.099.699.699.699.6
Percentage of Assets11.311.812.511.811.69.89.99.79.89.79.69.79.89.99.99.910.110.010.010.010.010.310.511.611.711.911.711.615.916.016.116.2
Percentage of Assets fe:RegulatedDistribution0.00.00.018.018.10.018.218.218.318.018.018.018.018.318.318.418.418.618.718.718.519.219.520.120.220.620.620.025.025.525.924.5

fe:RegulatedIndependentTransmission


Goodwillus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312016-09-302016-06-302015-12-312013-12-312013-09-302012-12-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302009-12-31
Value6146146146146145265265265265265260.00.00.00.00.00.00.00.0
Percentage of Goodwill10.910.910.910.910.99.49.48.28.28.28.20.00.00.00.00.00.00.00.0
Percentage of Assets1.41.51.51.51.41.01.01.01.01.01.00.00.00.00.00.00.00.00.0
Percentage of Assets fe:RegulatedIndependentTransmission0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:FiniteLivedIntangibleAssetsNet


Finite
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value738093105120331496588702803134
Percentage of FiniteLivedIntangibleAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.20.20.20.20.30.61.01.21.41.70.4

us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass

fe:NonUtilityGenerationContract


Finite
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value737883889399104109115120
Percentage of FiniteLivedIntangibleAssetsNet100.097.589.283.877.529.921.018.516.414.9
Percentage of Assets0.20.20.20.20.20.20.20.20.20.3
Percentage of Assets fe:NonUtilityGenerationContract0.00.00.00.00.00.00.00.00.00.0

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2020-12-312019-12-31
Value265231
Percentage of OperatingLeaseRightOfUseAsset100.0100.0
Percentage of Assets0.60.5

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value110671381293510396187058317524135725921053742871102811539071076123813791218130113451456116912791386167416981638166517191580158817161641751769818794666
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.51.71.92.22.51.51.72.11.91.01.51.52.51.72.02.42.71.72.12.32.62.32.52.62.82.32.52.73.33.43.33.33.43.23.33.63.51.61.61.72.31.9

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value827891882898918893810892965997909100510279249329771043944938100010759941034110212791190134114551250995950982159992510529181174100911221080872829
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.92.12.12.12.22.22.02.22.42.52.32.62.42.12.22.32.41.81.81.92.11.92.02.12.52.32.62.82.52.01.91.93.21.92.21.92.52.22.42.32.52.4

Accrued Income Taxes Current

us-gaap:AccruedIncomeTaxesCurrent

us-gaap:AccruedIncomeTaxesCurrent


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value640601563566545537416562533529508530571520518555580537439513519508467503490489397527485401338392543508436442558482399412326314
Percentage of AccruedIncomeTaxesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.41.31.31.31.31.01.41.31.31.31.41.41.21.21.31.31.00.91.01.01.00.91.00.91.00.81.01.00.80.70.81.11.00.90.91.21.00.80.90.90.9

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value500430772544369748624239398343244634580050685065407742554647765771267043675963895602587667896262556159796173773776377955753371327605592060825773485548635544516246985188
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.37.26.08.811.510.29.710.711.614.713.013.19.69.710.717.716.513.613.112.110.711.212.811.910.711.712.015.115.115.815.014.115.112.112.712.110.310.411.610.813.515.1

Long Term Debt Current

us-gaap:LongTermDebtCurrent

us-gaap:LongTermDebtCurrent


Long
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value14638050310821685116680414151999-1621.0-1486.0
Percentage of LongTermDebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.91.32.63.92.21.52.84.0-3.4-4.3

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityCurrent


Operating
Period End2020-12-312019-12-31
Value4232
Percentage of OperatingLeaseLiabilityCurrent100.0100.0
Percentage of Assets0.10.1

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent

us-gaap:OtherLiabilitiesCurrent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value56058636757214251084840105110261012557882722867619848660915687970694824605908693850612863621872599946103894261710099009806911062733711
Percentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.31.40.91.43.42.62.12.62.62.61.42.31.72.01.42.01.51.81.31.81.31.61.11.71.31.71.21.71.21.71.21.92.11.91.32.11.92.11.52.22.12.1

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value10092104701073610758108461057310579104201086410162974396151314011899117781165411589148831488714964149711506615115147791500714010141151408214261145901437214478145291374213295130521345612559126111248090158551
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets22.724.425.325.625.625.525.925.727.125.825.024.831.127.327.227.026.928.629.028.428.728.628.528.128.827.427.527.528.329.028.728.728.828.227.727.428.426.926.526.125.924.9

Long Term Debt

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

us-gaap:LongTermDebt

fe:GlobalHolding, fe:SeniorSecuredTermLoan, us-gaap:SeniorLoans


Long
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value108114190275300300350350350350350350350350
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.20.30.50.70.70.60.70.70.70.70.70.70.70.7
Percentage of Assets fe:GlobalHolding fe:SeniorSecuredTermLoan us-gaap:SeniorLoans0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:ConsolidatedEntities, us-gaap:StatementBusinessSegments

srt:ParentCompany, fe:OtherBusinessOperations


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value819978507850790071007100710072007100
Percentage of LongTermDebt7592.60.00.00.06228.10.00.00.03736.8
Percentage of Assets18.418.318.518.816.817.117.417.817.7
Percentage of Assets srt:ParentCompany fe:OtherBusinessOperations0.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:DebtInstrument

fe:PhaseInRecoveryBonds


Long
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312013-12-31
Value245268268280280292292304304315315327327339339350350362362374374386445
Percentage of LongTermDebt226.9235.10.00.00.0153.70.00.00.0114.50.00.00.0113.00.00.00.0120.70.00.00.0110.3127.1
Percentage of Assets0.60.60.60.70.70.70.70.80.80.70.70.80.80.80.70.70.70.70.70.70.70.70.9
Percentage of Assets fe:PhaseInRecoveryBonds0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value2237722389221682129720074198801950819088183151779617650179492226122218226461992119885197451966420217202442011819728197751982819757192581803417049
Percentage of LongTermDebt20719.40.00.00.017608.80.00.00.09639.50.00.00.08094.90.00.00.06628.30.00.00.06748.00.00.00.05665.15644.95502.35152.64871.1
Percentage of Assets50.352.152.350.647.547.947.747.145.745.145.346.352.750.952.346.146.138.038.338.438.838.237.237.738.038.637.535.233.8
Percentage of Assets us-gaap:CarryingReportedAmountFairValueDisclosure0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:EstimateOfFairValueFairValueDisclosure


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value2546526161262782357622928229102189020691192661876118876194872303822994231642002919829214652162721821215192152521195219112173321363208161932117957
Percentage of LongTermDebt23578.70.00.00.020112.30.00.00.010140.00.00.00.08377.50.00.00.06609.70.00.00.07173.00.00.00.06209.46103.75947.45520.35130.6
Percentage of Assets57.360.962.056.054.255.253.551.148.147.648.450.254.552.753.546.446.041.342.141.441.240.940.041.741.741.740.537.735.6
Percentage of Assets us-gaap:EstimateOfFairValueFairValueDisclosure0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Long Term Debt And Capital Lease Obligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations


Long
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value221312220321980208211961819422190531881417751166081646116740211152108920582177621819218532183481887819192190931857019130191761853118415168041583115291154491581415179156271515915527157161582316491175351257912008
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets49.851.751.849.546.446.846.646.544.342.142.243.150.048.347.541.142.235.735.735.836.836.335.036.436.836.235.832.831.430.330.831.430.132.131.532.633.233.934.636.636.135.0

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value303628762774284929002502
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0
Percentage of Assets7.16.86.66.77.06.2

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent


Pension
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value334533423401345530652403241424172906274227172717397538143784375637194080417741354245386138363817393227542732271326893104308830703080227122572240282320452134231318681534
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.57.88.08.27.25.85.96.07.37.07.07.09.48.78.78.78.67.98.17.88.17.37.27.37.55.45.35.35.36.26.26.16.14.74.74.76.04.44.54.85.44.5

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value163711171321135716671755190919022057159111651057171814351584160617041269141914301555119113731332159012581494153217781716170317511836190419802011207221272208233512191226
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.72.63.13.23.94.24.74.75.14.03.02.74.13.33.73.73.92.42.82.73.02.32.62.53.02.52.93.03.53.43.43.53.63.94.14.24.44.64.64.93.53.6

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent


Operating
Period End2020-12-312019-12-31
Value263241
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0
Percentage of Assets0.60.6

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-312019-12-31
Value4940
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0100.0
Percentage of Assets0.10.1

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-312019-12-31
Value4640
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0100.0
Percentage of Assets0.10.1

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-312019-12-31
Value3836
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0100.0
Percentage of Assets0.10.1

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-312019-12-31
Value3629
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0100.0
Percentage of Assets0.10.1

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-12-312019-12-31
Value147154
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0100.0
Percentage of Assets0.30.4

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2020-12-312019-12-31
Value305273
Percentage of OperatingLeaseLiability100.0100.0
Percentage of Assets0.70.6

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-312019-12-31
Value366339
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0
Percentage of Assets0.80.8

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-12-312019-12-31
Value6166
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0100.0
Percentage of Assets0.10.2

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value72377188714368146975727272696932681468737699737539256406632061396241115031140712463124211262712530123481242012702126831260212692125441279912996130841343313497133231328013046129981272985458559
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets16.316.716.816.216.517.517.817.117.017.419.819.09.314.714.614.214.522.122.223.723.824.023.623.523.824.824.724.625.224.925.525.826.027.628.127.928.128.027.326.624.625.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-312015-12-312014-12-31
Value3.06.08.0112937414652738797150186258
Percentage of StockholdersEquity0.00.10.10.20.40.50.60.70.81.11.12.52.41.52.1
Percentage of Assets0.00.00.00.00.10.10.10.10.10.20.20.20.30.40.5
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312016-12-31
Value-8.0-8.0-8.0-9.0-9.0-10.0-10.0-10.0-11.0-22.0-28.0
Percentage of StockholdersEquity-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.2-0.6-0.4
Percentage of Assets-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1
Percentage of Assets us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-5.0-2.00.02.02027313641617386142174171246284385426-1539.0-1415.0-1380.0-50.0
Percentage of StockholdersEquity-0.1-0.00.00.00.30.40.40.50.60.90.91.23.62.81.42.02.22.93.2-18.0-16.50.00.0
Percentage of Assets-0.0-0.00.00.00.00.10.10.10.10.20.20.20.30.40.30.50.60.80.9-4.4-4.1-4.10.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value1007610266106731065110868110471141111381115301170811975119371000110555995298479776976997655444544854735509
Percentage of StockholdersEquity139.2142.8149.4156.3155.8151.9157.0164.2169.2170.3155.5161.9254.8169.180.179.377.074.773.563.763.70.00.0
Percentage of Assets22.723.925.225.325.726.627.928.128.829.730.730.823.724.519.118.919.419.420.615.615.916.30.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value5454545454545353515148484444424242424231313131
Percentage of StockholdersEquity0.70.80.80.80.80.70.70.80.70.70.60.71.10.70.30.30.30.30.30.40.40.00.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-2888.0-3130.0-3584.0-3893.0-3967.0-3856.0-4247.0-4559.0-4879.0-5017.0-4559.0-4858.0-6262.0-4532.0225622852590288830474609449541593487
Percentage of StockholdersEquity-39.9-43.5-50.2-57.1-56.9-53.0-58.4-65.8-71.6-73.0-59.2-65.9-159.5-72.618.218.420.422.122.953.952.50.00.0
Percentage of Assets-6.5-7.3-8.5-9.2-9.4-9.3-10.4-11.3-12.2-12.7-11.7-12.5-14.8-10.54.34.45.15.76.413.213.112.40.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2020-12-312019-12-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value7237697536681461738639251511631756241115031140712464124221262812531123501242212704126851260512695125471280313000130931344913512133391329913015129501268985138557
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets16.316.50.117.00.20.20.29.30.30.40.414.522.122.223.723.824.023.623.523.824.824.724.625.224.925.525.826.027.628.128.028.127.927.226.524.524.9

Additional Paid In Capital Common Stock

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AdditionalPaidInCapitalCommonStock


Additional
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value10076102661067310651108681104711411113811153011708119751193710001997410272102531055510012998499639952992698959871984798369817979397769755974497399769975897569754976597829782977954445448
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets22.723.925.225.325.726.627.928.128.829.730.730.823.722.923.723.724.519.319.418.919.118.818.718.818.919.219.119.119.419.419.419.319.420.020.320.520.621.020.620.415.615.9

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-2888.0-3130.0-3584.0-3893.0-3967.0-3856.0-4247.0-4559.0-4900.0-5017.0-4559.0-4858.0-6262.0-3763.0-4159.0-4333.0-4532.01264119022792256248223912205228525922560249625902448269028542888326633103122304746584607442646094495
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-6.5-7.3-8.5-9.2-9.4-9.3-10.4-11.3-12.2-12.7-11.7-12.5-14.8-8.6-9.6-10.0-10.52.42.34.34.34.74.54.24.45.15.04.95.14.95.45.75.76.76.96.56.410.09.79.213.213.1

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-5.0-2.00.02.02027313641617386142151163175174184191179171177202230246232264271284299323361385367389405426-1436.0-1433.0-1518.0-1539.0-1415.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.0-0.00.00.00.00.10.10.10.10.20.20.20.30.30.40.40.40.40.40.30.30.30.40.40.50.50.50.50.60.60.60.70.80.80.80.80.9-3.1-3.0-3.2-4.4-4.1

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value572701710-560.07301112807-182.0852846592-880.010461280697785791112082263811301327797193-413.0834119854049110031215352506
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.023.528.5-21.327.338.033.0-6.531.428.322.5-30.439.034.521.122.123.428.624.216.531.932.223.05.0-10.422.025.413.30.00.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-737.0-765.0-747.0-659.0-792.0-745.0-706.0-630.0-781.0-672.0-422.0-1143.0-535.0-670.0-749.0-762.0-805.0-709.0-902.0-865.0-835.0-594.0-945.0-748.0-534.0-401.0-20.0-676.0141-503.0-478.0-491.0-476.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-28.4-25.6-30.0-25.1-29.6-25.5-28.8-22.5-28.8-22.5-16.1-39.5-20.0-18.0-22.6-21.5-23.9-18.1-26.5-22.4-23.6-14.4-27.3-19.2-13.4-10.6-0.4-16.70.00.00.00.00.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value167019517725-9.0-91.0163593-129.0-11.0-145.01679-321.0-325.02.0-58.0-338.0-59.0133242-250.0-741.0152560819-522.0-1363.0-489.0-550.0-113.0-386.0110-594.0
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax64.36.50.727.6-0.3-3.16.721.1-4.8-0.4-5.558.1-12.0-8.80.1-1.6-10.0-1.53.96.3-7.1-18.04.414.420.5-13.8-28.9-12.00.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value1505131-20.0-494.0-71.0276264-219.0-58.0163
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax58.04.4-0.8-18.8-2.79.410.8-7.8-2.15.5

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value39520230729514836735734538139932428045245640039255751846745545351444442563234332226638962837435219333347
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInInventories


Increase
Period End2020-12-312020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value9.05.023-15.0171219-15.08.0-36.00.0-4.021-11.04.0-46.05.0-4.047-32.030-30.046-31.062-12.021-75.0-16.0-26.0-13.0-46.0-9.011848-38.016-40.0-8.0-11.0-25.042
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value572701710-560.07301112807-182.0852846592-880.010461280697785791112082263811301327797193-413.0834119854049110031215352506
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax22.023.528.5-21.327.338.033.0-6.531.428.322.5-30.439.034.521.122.123.428.624.216.531.932.223.05.0-10.422.025.413.30.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value24245430974-111.0391312320138-458.02991369-2499.0396174205-5796.0380-1089.0328-226.0395187222-306.033364208142218-164.0196-148.04251873069851118150185179265155239234414119
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.315.212.42.8-4.213.412.711.45.1-15.311.447.3-93.210.75.35.8-171.79.7-32.08.5-6.49.65.45.7-8.88.61.85.03.95.4-4.75.3-4.99.94.87.72.610.84.50.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value-2.0-3.0-18.0-4.0-5.0-6.0-13.0-15.0-13.0-12.0-10.0-12.0
Percentage of NetIncomeLoss-0.4-1.0-24.3-1.0-1.6-1.92.8-5.0-0.9-3.0-5.7-5.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.1-0.1-0.7-0.1-0.2-0.2-0.4-0.6-0.4-0.3-0.3-0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.01.00.00.00.01.0
Percentage of NetIncomeLoss0.00.30.00.00.00.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedGainLossNetCashFlowHedgeParent0.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value45430974391312320-458.02991369
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax15.212.42.813.412.711.4-15.311.447.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-737.0-765.0-747.0-659.0-792.0-745.0-706.0-630.0-781.0-672.0-422.0-1143.0-535.0-670.0-749.0-762.0-805.0-709.0-902.0-865.0-835.0-594.0-945.0-748.0-534.0-401.0-20.0-676.0141-503.0-478.0-491.0-476.0
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-28.4-25.6-30.0-25.1-29.6-25.5-28.8-22.5-28.8-22.5-16.1-39.5-20.0-18.0-22.6-21.5-23.9-18.1-26.5-22.4-23.6-14.4-27.3-19.2-13.4-10.6-0.4-16.70.00.00.00.00.0

Payments To Acquire Productive Assets

us-gaap:PaymentsToAcquireProductiveAssets

us-gaap:PaymentsToAcquireProductiveAssets


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value678687676616753684674554733635724583740593666588679664794698679539818668839664988821678548586826992775412589749512569449496471489508
Percentage of PaymentsToAcquireProductiveAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireProductiveAssets us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value18209.015205.05.0511214218.05.0179.015
Percentage of PaymentsToAcquireProductiveAssets2.63.01.52.23.00.90.87.02.12.43.21.40.82.11.32.8

us-gaap:PaymentsToAcquireProductiveAssets us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value391386338365354318356391264286304264303287241292
Percentage of PaymentsToAcquireProductiveAssets56.957.154.953.452.557.456.154.045.348.245.644.945.636.134.554.2

us-gaap:OperatingSegments, fe:RegulatedTransmission


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value278270269304300231262282292248245224246277279149
Percentage of PaymentsToAcquireProductiveAssets40.539.943.744.444.541.741.339.050.141.836.838.137.034.940.027.6

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value167019517725-9.0-91.0163593-129.0-11.0-145.01679-321.0-325.02.0-58.0-338.0-59.0133242-250.0-741.0152560819-522.0-1363.0-489.0-550.0-113.0-386.0110-594.0
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax64.36.50.727.6-0.3-3.16.721.1-4.8-0.4-5.558.1-12.0-8.80.1-1.6-10.0-1.53.96.3-7.1-18.04.414.420.5-13.8-28.9-12.00.00.00.00.00.0

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:ProceedsFromIssuanceOfLongTermDebt


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value0.02501175200020015055014008501744500.0625550325025014555210.00.02278842000.07506411670146710005004451800904781820.01.0100286217848
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value0.025011752000200150
Percentage of ProceedsFromIssuanceOfLongTermDebt0.0100.0100.0100.0100.0100.0

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.0283047785.02712962833027775147658097652421113144365503198489244486971374364899386941012956701247301632857964335959315298109
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RepaymentsOfLongTermDebt us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


Repayments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value4.0283047785.027
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0

Payments Of Dividends Common Stock

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsOfDividendsCommonStock


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value211212211211205206202201184184172171161159160159153153153152152152151152152150151151230230230230230230230230230231230190167168167168
Percentage of PaymentsOfDividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:EffectiveIncomeTaxRateContinuingOperations


Effective
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-2.220.10.1771.667-0.0150.2160.1920.208-0.0510.2560.3010.587-1.4630.3760.4020.3810.3980.1070.394-0.0230.3640.3810.393-0.5490.3130.2890.282-0.0140.2690.2610.3720.0030.421
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value309528492502135937656773
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value1391641588084343448434442191
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:AmortizationDeferralOfRegulatoryAsset

fe:AmortizationDeferralOfRegulatoryAsset


Amortization
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-27.0-91.01352-164.043375.03867-107.0
Percentage of AmortizationDeferralOfRegulatoryAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:AmortizationDeferralOfRegulatoryAsset us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Amortization
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-91.010.04942343.065-107.0
Percentage of AmortizationDeferralOfRegulatoryAsset100.076.994.297.791.960.097.0100.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Amortization
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value0.03.03.01.03.02.02.00.0
Percentage of AmortizationDeferralOfRegulatoryAsset-0.023.15.82.38.140.03.0-0.0

fe:AmountPaidtoSettleAgreementsandTaxSharingPaymentstoSubsidiaryDebtors

fe:AmountPaidtoSettleAgreementsandTaxSharingPaymentstoSubsidiaryDebtors


Amount
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.09780.00.0
Percentage of AmountPaidtoSettleAgreementsandTaxSharingPaymentstoSubsidiaryDebtors0.00.00.0100.00.00.0

fe:AssetAcquisitionOwnershipInterestAcquired fe:AssetAcquisition, us-gaap:StatementBusinessSegments

fe:AssetAcquisitionOwnershipInterestAcquired

fe:YardsCreekEnergyLLCHydroGenerationFacility, fe:RegulatedDistribution


Asset
Period End2020-12-312020-09-30
Value049.5
Percentage of AssetAcquisitionOwnershipInterestAcquired0.0100.0

fe:CappingOfGasOneEmissionsUnderCrossStateAirPollutionRule us-gaap:LossContingenciesByNatureOfContingency

fe:CappingOfGasOneEmissionsUnderCrossStateAirPollutionRule

fe:NationalAmbientAirQualityStandards


Capping
Period End2020-12-31
Value0
Percentage of CappingOfGasOneEmissionsUnderCrossStateAirPollutionRule0.0

fe:CappingOfGasTwoEmissionsUnderCrossStateAirPollutionRule us-gaap:LossContingenciesByNatureOfContingency

fe:CappingOfGasTwoEmissionsUnderCrossStateAirPollutionRule

fe:NationalAmbientAirQualityStandards


Capping
Period End2020-12-31
Value0
Percentage of CappingOfGasTwoEmissionsUnderCrossStateAirPollutionRule0.0

fe:CollateralPostedDueToCreditRatingDowngrade

fe:CollateralPostedDueToCreditRatingDowngrade


Collateral
Period End2020-12-31
Value19
Percentage of CollateralPostedDueToCreditRatingDowngrade100.0

fe:DebtandEquitySecuritiesRealizedGainLossSalesProceeds

fe:DebtandEquitySecuritiesRealizedGainLossSalesProceeds


Debtand
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1416.026131131204149153173261175191141269313
Percentage of DebtandEquitySecuritiesRealizedGainLossSalesProceeds100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DebtandEquitySecuritiesRealizedGains

fe:DebtandEquitySecuritiesRealizedGains


Debtand
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value8.00.00.04.0788.05.07.010.03.09.0194.02029
Percentage of DebtandEquitySecuritiesRealizedGains100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DebtandEquitySecuritiesRealizedLosses

fe:DebtandEquitySecuritiesRealizedLosses


Debtand
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1.00.02.05.0137.05.06.0147.011163.01129
Percentage of DebtandEquitySecuritiesRealizedLosses100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DeconsolidationGainLossAmountBeforeTax us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

fe:DeconsolidationGainLossAmountBeforeTax

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Deconsolidation
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.0228.010.0-33.0-14.0-1183.00.0320
Percentage of DeconsolidationGainLossAmountBeforeTax0.0100.0100.0100.0100.0100.0100.00.0100.0

fe:DeconsolidationSettlementConsiderationandServicesCredit us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

fe:DeconsolidationSettlementConsiderationandServicesCredit

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Deconsolidation
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.0-3.04.0-22.0-8.0-10.0331411830.00.0
Percentage of DeconsolidationSettlementConsiderationandServicesCredit0.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

fe:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationIncreaseDecreaseinDiscountRate

fe:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationIncreaseDecreaseinDiscountRate


Defined
Period End2020-12-31
Value-29.0
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationIncreaseDecreaseinDiscountRate100.0

fe:DefinedBenefitPlanBenefitObligationOneTimeTerminationBenefit us-gaap:RetirementPlanType

fe:DefinedBenefitPlanBenefitObligationOneTimeTerminationBenefit

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value000-8000000.000
Percentage of DefinedBenefitPlanBenefitObligationOneTimeTerminationBenefit0.00.00.0100.00.00.0

fe:DefinedBenefitPlanNetPeriodicBenefitCostExcludingCapitalizedAmounts us-gaap:RetirementPlanType

fe:DefinedBenefitPlanNetPeriodicBenefitCostExcludingCapitalizedAmounts

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value-8.0-8.01.0-10.0-10.0-10.0-15.0-21.0-21.0-14.0
Percentage of DefinedBenefitPlanNetPeriodicBenefitCostExcludingCapitalizedAmounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value-56.0-62.0358-11.0-14.06.05.0-18.0-14.030
Percentage of DefinedBenefitPlanNetPeriodicBenefitCostExcludingCapitalizedAmounts700.0775.035800.0110.0140.0-60.0-33.385.766.7-214.3

fe:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryReturnSeekingAssetsSoldDuringPeriod

fe:DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryReturnSeekingAssetsSoldDuringPeriod


Defined
Period End2020-09-30
Value800
Percentage of DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryReturnSeekingAssetsSoldDuringPeriod100.0

fe:DefinedBenefitPlanPlanAssetsPeriodIncreaseDecreaseIncludingDiscontinuedOperations

fe:DefinedBenefitPlanPlanAssetsPeriodIncreaseDecreaseIncludingDiscontinuedOperations


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value540.00.04230.00.0
Percentage of DefinedBenefitPlanPlanAssetsPeriodIncreaseDecreaseIncludingDiscontinuedOperations100.00.00.0100.00.00.0

fe:DiscontinuedOperationTaxEffectOfDiscontinuedOperationAdjustmentsRelatedToIntercompanyTaxSharing

fe:DiscontinuedOperationTaxEffectOfDiscontinuedOperationAdjustmentsRelatedToIntercompanyTaxSharing


Discontinued
Period End2020-12-312020-09-30
Value126.0
Percentage of DiscontinuedOperationTaxEffectOfDiscontinuedOperationAdjustmentsRelatedToIntercompanyTaxSharing100.0100.0

fe:DisposalGroupIncludingDiscontinuedOperationFuelCosts us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

fe:DisposalGroupIncludingDiscontinuedOperationFuelCosts

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Disposal
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.00.00.06.03550203535525.0116208237180164
Percentage of DisposalGroupIncludingDiscontinuedOperationFuelCosts0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DisposalGroupIncludingDiscontinuedOperationOtherOperatingExpenses us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

fe:DisposalGroupIncludingDiscontinuedOperationOtherOperatingExpenses

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Disposal
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.00.00.06.021161610.021240.0347402290282492
Percentage of DisposalGroupIncludingDiscontinuedOperationOtherOperatingExpenses0.00.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

fe:FairValueInputsRTOAuctionClearingPrices us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:ValuationTechnique

fe:FairValueInputsRTOAuctionClearingPrices

srt:Maximum, fe:Ftrs, us-gaap:FairValueInputsLevel3, fe:Model


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value2200000.00.4-0.12.1-0.20.9
Percentage of FairValueInputsRTOAuctionClearingPrices100.0100.0100.0100.0100.0100.0

srt:Minimum, fe:Ftrs, us-gaap:FairValueInputsLevel3, fe:Model


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value400000.0-0.10.3-0.10.10.1
Percentage of FairValueInputsRTOAuctionClearingPrices18.2-25.0-300.0-4.8-50.011.1

srt:WeightedAverage, fe:Ftrs, us-gaap:FairValueInputsLevel3, fe:Model


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value1100000.00.20.50.50.10.2
Percentage of FairValueInputsRTOAuctionClearingPrices50.050.0-500.023.8-50.022.2

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityPurchases us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityPurchases

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312014-09-302013-12-312013-09-30
Value0.00.05.00.00.00.02.00.00.00.00.00.00.01.01.0-1.02.0-1.01.0-3.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityPurchases0.00.0100.00.00.00.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitySettlements us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitySettlements

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.0-1.0-2.04.00.0-2.0-1.010.00.0-1.01.03.01.0-1.0-4.04.02.0-2.0-7.00.0-5.00.04.0307.0114.01.0-1.01.0-1.03.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitySettlements100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:NonUtilityGenerationContract, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.07.0-13.0-13.0-11.0-8.0-10.0-10.0-8.0-9.0-9.0-7.0-9.0-11.0-8.0-10.0-9.0-11.0-11.0-13.0-18.0-17.0-15.0-12.0-21.0-24.0-16.010.0-21.0-14.0-19.0-23.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilitySettlements0.0-700.0650.0-325.00.0400.01000.0-100.00.0900.0-900.0-233.3-900.01100.0200.0-250.0-450.0550.0157.10.0360.00.0-375.0-40.0-300.0-218.2-400.01000.02100.0-1400.01900.0-766.7

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityUnrealizedGainLoss us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityUnrealizedGainLoss

fe:NonUtilityGenerationContract, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.0-7.07.03.03.0-3.04.07.00.0-4.00.02.0-4.04.04.06.00.06.0-1.01212207.010.017111.0-27.011-6.030-18.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityUnrealizedGainLoss0.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisUnrealizedGainLoss us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

fe:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisUnrealizedGainLoss

fe:NonUtilityGenerationContract, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.07.0-7.0-3.0-3.03.0-4.0-7.00.04.00.0-2.04.0-4.0-4.0-6.02.0-6.01.0-12.0-11.0-20.0-7.0-9.0-17.0-10.00.027-13.08.0-38.018
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisUnrealizedGainLoss0.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

fe:IncomeTaxExpenseBenefitfromDeconsolidationGainLossIncludingWorthlessStockDeduction us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

fe:IncomeTaxExpenseBenefitfromDeconsolidationGainLossIncludingWorthlessStockDeduction

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value30-6.0-1.0-36.0-53.0-15.025-9.0-44.0-349.00.0-919.0
Percentage of IncomeTaxExpenseBenefitfromDeconsolidationGainLossIncludingWorthlessStockDeduction100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

fe:IncreaseDecreasetoNetPeriodicBenefitCostBasedonMarktoMarketAdjustment us-gaap:RetirementPlanType

fe:IncreaseDecreasetoNetPeriodicBenefitCostBasedonMarktoMarketAdjustment

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value-23.00.00.0370.00.0
Percentage of IncreaseDecreasetoNetPeriodicBenefitCostBasedonMarktoMarketAdjustment100.00.00.0100.00.00.0

us-gaap:PensionPlansDefinedBenefit


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value770.00.03860.00.0
Percentage of IncreaseDecreasetoNetPeriodicBenefitCostBasedonMarktoMarketAdjustment-334.80.00.01043.20.00.0

fe:InvestmentIncomeFromTrusts

fe:InvestmentIncomeFromTrusts


Investment
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value4.04.09.05.08.010.0119.010.01110.010.026242523252725232625252523242425272622261918181510.0202824231916
Percentage of InvestmentIncomeFromTrusts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:PublicUtilitiesExpectedCostOfTheProgram dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments

fe:PublicUtilitiesExpectedCostOfTheProgram

fe:JcpAndL, stpr:NJ, fe:AdvancedMeteringInfrastructure, fe:NewJerseyBoardofPublicUtilities, fe:RegulatedDistribution


Public
Period End2020-08-27
Value418
Percentage of PublicUtilitiesExpectedCostOfTheProgram100.0

fe:PublicUtilitiesNumberOfMetersToBeDeployed dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments

fe:PublicUtilitiesNumberOfMetersToBeDeployed

fe:JcpAndL, stpr:NJ, fe:AdvancedMeteringInfrastructure, fe:NewJerseyBoardofPublicUtilities, fe:RegulatedDistribution


Public
Period End2020-08-27
Value1200000.0
Percentage of PublicUtilitiesNumberOfMetersToBeDeployed100.0

fe:PublicUtilitiesPlantConstructionPlantCapacity dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:PublicUtilitiesPlantConstructionPlantCapacity

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:IntegratedResourcePlan, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-12-30
Value50.0
Percentage of PublicUtilitiesPlantConstructionPlantCapacity100.0

fe:PublicUtilitiesProgramStudyFindingsSubmittedAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding

fe:PublicUtilitiesProgramStudyFindingsSubmittedAmount

fe:Pe, stpr:MD, fe:DepreciationExpenseStudy


Public
Period End2020-09-22
Value36
Percentage of PublicUtilitiesProgramStudyFindingsSubmittedAmount100.0

fe:PublicUtilitiesRecoveryOfDeferredIncrementalUncollectibleAndOtherRelatedCosts dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:PublicUtilitiesRecoveryOfDeferredIncrementalUncollectibleAndOtherRelatedCosts

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:ExpandedNetEnergyCost, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-08-28
Value10
Percentage of PublicUtilitiesRecoveryOfDeferredIncrementalUncollectibleAndOtherRelatedCosts100.0

fe:PublicUtilitiesRequestedAnnualRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:PublicUtilitiesRequestedAnnualRateIncreaseDecreaseAmount

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:ExpandedNetEnergyCost, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-12-30
Value-2600000.0
Percentage of PublicUtilitiesRequestedAnnualRateIncreaseDecreaseAmount100.0

fe:PublicUtilitiesSettledDecreaseInRegulatoryLiability dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency

fe:PublicUtilitiesSettledDecreaseInRegulatoryLiability

fe:JcpAndL, stpr:NJ, fe:NewJerseyBoardofPublicUtilities


Public
Period End2020-10-16
Value86
Percentage of PublicUtilitiesSettledDecreaseInRegulatoryLiability100.0

fe:PublicUtilitiesSettledDecreaseInRegulatoryLiability dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType

fe:JcpAndL, stpr:NJ, fe:NewJerseyBoardofPublicUtilities, us-gaap:SubsequentEvent


Public
Period End2020-10-16
Value86
Percentage of PublicUtilitiesSettledDecreaseInRegulatoryLiability100.0

fe:PublicUtilitiesSettledRevenueIncreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency

fe:PublicUtilitiesSettledRevenueIncreaseAmount

fe:JcpAndL, stpr:NJ, fe:NewJerseyBoardofPublicUtilities


Public
Period End2020-10-16
Value94
Percentage of PublicUtilitiesSettledRevenueIncreaseAmount100.0

fe:PublicUtilitiesSettledRevenueIncreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType

fe:JcpAndL, stpr:NJ, fe:NewJerseyBoardofPublicUtilities, us-gaap:SubsequentEvent


Public
Period End2020-10-16
Value94
Percentage of PublicUtilitiesSettledRevenueIncreaseAmount100.0

fe:TaxCutsandJobsActChangeinTaxRateRefundofRevenue us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

fe:TaxCutsandJobsActChangeinTaxRateRefundofRevenue

us-gaap:OperatingSegments, fe:RegulatedDistribution


Tax
Period End2020-09-302019-09-30
Value1.04.0
Percentage of TaxCutsandJobsActChangeinTaxRateRefundofRevenue100.0100.0

fe:TaxCutsandJobsActChangeinTaxRateRefundofRevenue us-gaap:StatementBusinessSegments

fe:RegulatedTransmission


Tax
Period End2020-09-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3.08.04.02.05.0122.02.04.0
Percentage of TaxCutsandJobsActChangeinTaxRateRefundofRevenue300.00.0100.00.00.00.00.00.00.0

us-gaap:AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease

us-gaap:AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease


Allowance
Period End2020-12-312020-09-302020-06-30
Value582043
Percentage of AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease us-gaap:PublicUtilitiesRegulatoryProceeding

fe:FutureRecoveryOfIncrementalCosts


Allowance
Period End2020-12-312020-09-30
Value5013
Percentage of AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease86.265.0

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries


Allowance
Period End2020-09-302020-06-302020-03-31
Value1110.014
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs


Allowance
Period End2020-09-302020-06-302020-03-31
Value232735
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs100.0100.0100.0

us-gaap:DeconsolidationGainOrLossAmount us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DeconsolidationGainOrLossAmount

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Deconsolidation
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value30-6.02.0507523-15.0-24.030-834.00.012390.00.00.00.0
Percentage of DeconsolidationGainOrLossAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.00.00.00.0

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:DeferredIncomeTaxesAndTaxCredits


Deferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-11.012181-78.01.08971912313549278386229110114-3381.0246-134.0206-144.020992127-165.0168-22.0181129-5.0-15.0134-65.02891582651628438117121110010059
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-4.0-4.0-5.0-33.0-9.0-9.0-9.0-9.0-21.0-20.0-20.0-20.0-21.0-20.0-20.0-20.0-20.0-20.0-20.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.01.01.010.01.02.02.02.01.02.02.02.01.02.02.02.02.02.02.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-0.0-25.0-20.0-30.3-11.1-22.2-22.2-22.2-4.8-10.0-10.0-10.0-4.8-10.0-10.0-10.0-10.0-10.0-10.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value8.09.08.08.08.07.07.07.09.07.07.08.08.07.07.08.07.07.08.0
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value154156155153135135135135142144144144112112112112102100100
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets1925.01733.31937.51912.51687.51928.61928.61928.61577.82057.12057.11800.01400.01600.01600.01400.01457.11428.61250.0

us-gaap:DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease

us-gaap:DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-54.00.00.0-423.0-674.00.00.00.0-144.00.00.00.01410.00.00.01470.00.00.02420.00.00.08350.00.00.0-256.00.00.00.06090.00.00.05070.00.00.0
Percentage of DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease100.00.00.0100.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value3.04.04.04.06.06.05.05.07.06.06.06.06.07.07.07.08.07.08.0
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value717170759493939393939393999797971009999
Percentage of DefinedBenefitPlanInterestCost2366.71775.01750.01875.01566.71550.01860.01860.01328.61550.01550.01550.01650.01385.71385.71385.71250.01414.31237.5

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-31.0-8.0-8.01.09.0-9.0-10.0-10.0-101.0-14.0-20.0-21.0-8.0-19.0-19.0-20.0-3.0-18.0-19.0
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value41-37.0-36.03786658.07.023245287.07.01483939392264949
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-132.3462.5450.037800.07388.9-88.9-70.0-230.0-242.6-200.0-35.0-33.3-1850.0-205.3-205.3-195.0-7533.3-272.2-257.9

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value1.01.01.01.00.01.01.01.02.01.01.01.02.01.01.01.01.02.01.0
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value47474852494848485656565652525252474848
Percentage of DefinedBenefitPlanServiceCost4700.04700.04800.05200.00.04800.04800.04800.02800.05600.05600.05600.02600.05200.05200.05200.04700.02400.04800.0

us-gaap:Depreciation

us-gaap:Depreciation


Depreciation
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value320316321317310304309297293283299294293289281275339311334329313328322319316308302294293316302294287282292279283297287220
Percentage of Depreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Depreciation us-gaap:ConsolidationItems

us-gaap:CorporateNonSegment


Depreciationus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value0.00.02.00.01.02.01.0191917191816171515
Percentage of Depreciation0.00.00.60.00.30.70.46.46.55.96.86.55.15.14.64.6

us-gaap:MaterialReconcilingItems


Depreciationus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value1417161817171618180.00.00.00.00.00.00.0
Percentage of Depreciation4.45.35.05.95.55.75.76.06.10.00.00.00.00.00.00.0

us-gaap:Depreciation us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, fe:RegulatedDistribution


Depreciationus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value223226223215220209202200196183179178171168167174
Percentage of Depreciation70.670.470.370.771.270.471.466.966.763.363.764.755.050.350.853.0

us-gaap:OperatingSegments, fe:RegulatedTransmission


Depreciationus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-30
Value79787671716964626159545145464541
Percentage of Depreciation25.024.324.023.423.023.222.620.720.720.419.218.514.513.813.712.5

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax us-gaap:DisposalGroupClassification, us-gaap:PublicUtility, us-gaap:StatementBusinessSegments

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax

us-gaap:DisposalGroupDisposedOfBySaleNotDiscontinuedOperations, fe:ThreeMileIslandUnit2, fe:RegulatedDistribution


Discontinued
Period End2020-12-31
Value33
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax100.0

us-gaap:DiscontinuedOperationTaxEffectOfDiscontinuedOperation

us-gaap:DiscontinuedOperationTaxEffectOfDiscontinuedOperation


Discontinued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value-30.06.01.0-36.0-51.02.0395.02551-354.030-890.08213715-26.00.00.00.00.0690.03.04.02.00.02.0
Percentage of DiscontinuedOperationTaxEffectOfDiscontinuedOperation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.00.0100.0100.0100.00.0100.0

us-gaap:DisposalGroupIncludingDiscontinuedOperationOtherIncome us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupIncludingDiscontinuedOperationOtherIncome

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Disposal
Period End2020-09-302020-06-302019-09-302019-06-30
Value002000000.010000000.0
Percentage of DisposalGroupIncludingDiscontinuedOperationOtherIncome0.00.0100.0100.0

us-gaap:DisposalGroupIncludingDiscontinuedOperationRevenue us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupIncludingDiscontinuedOperationRevenue

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Disposal
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.00.00.07.041623154558311622756788680689
Percentage of DisposalGroupIncludingDiscontinuedOperationRevenue0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash

us-gaap:DividendsCommonStockCash


Dividends
Period End2020-09-302020-03-312019-09-302019-03-312018-09-302018-03-31
Value424211411202368343
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Dividends
Period End2020-09-302020-03-312019-09-302019-03-312018-09-302018-03-31
Value424211411202368343
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0

us-gaap:ExciseTaxesCollected

us-gaap:ExciseTaxesCollected


Excise
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value861008492901008110293104871029710291100961119210796109961159910599117112117107114104123107121115137116119100120
Percentage of ExciseTaxesCollected100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312014-09-302013-12-312013-09-30
Value0.00.07.00.00.00.06.00.00.00.0-1.01.0-1.02.00.00.00.00.01.0-1.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases0.00.0100.00.00.00.0100.00.00.00.0100.0100.0100.0100.00.00.00.00.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value1.00.00.04.01.00.00.010.01.01.01.03.01.00.00.07.07.0-2.01.05.01.04.07.03610.0169.03.02.03.02.06.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements100.00.00.0100.0100.00.00.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312014-09-302013-12-312013-09-30
Value0.00.02.00.00.00.04.00.00.00.0-1.01.0-1.01.0-1.01.0-2.01.00.02.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases0.00.0100.00.00.00.0100.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.01.02.00.01.02.01.00.01.02.00.00.00.01.04.03.05.00.08.05.06.04.03.06.03.05.05.02.03.02.03.03.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements0.0100.0100.00.0100.0100.0100.00.0100.0100.00.00.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:NonUtilityGenerationContract, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value0.0-7.01313118.010.010.08.09.09.07.09.0118.01110.0121113191716132125187.022172125
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements0.0-700.0650.00.01100.0400.01000.00.0800.0450.00.00.00.01100.0200.0366.7200.00.0137.5260.0316.7425.0533.3216.7700.0500.0360.0350.0733.3850.0700.0833.3

us-gaap:FuelCosts

us-gaap:FuelCosts


Fuel
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value931017798115122129131134137177187309363343368397450438381477482383513569544550617581657628630638636656541597632635453348400350334
Percentage of FuelCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax


Income
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-6.02.050702.0-29.0-24.0-44.0-845.0111239-1438.095-46.00.00.00.00.00.00.00.00.0860.09.04.04.05.03.04.04.0
Percentage of IncomeLossFromDiscontinuedOperationsNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value30-6.02.050702.0-29.0-35.0-44.0-845.0321192-1438.095-45.0-52.0
Percentage of IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DiscontinuedOperationsDisposedOfByMeansOtherThanSale, fe:FESandFENOC


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value30-6.02.050702.0-29.0-35.0-44.0-845.0321192-1438.095-45.0-52.0
Percentage of IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.06-0.0100.090.130.01-0.05-0.07-0.09-1.680.062.51-3.230.21-0.1-0.1200000000.2100.020.010.010.010.010.010.01
Percentage of IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare


Income
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.06-0.0100.090.130-0.05-0.07-0.09-1.680.062.5-3.230.21-0.1-0.1200000000.200.020.010.010.010.010.010.01
Percentage of IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance

us-gaap:IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance


Income
Period End2020-12-31
Value-101.0
Percentage of IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance100.0

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value96108-24.0-51.0-43.0-11.0-125.0-92.0-6.027412-32.011210.0-15.0-68.0-23.0135-100.0-1.0-177.01.0-105.097-49.0-134.0-124.0168107-118.09134-28.0-64.0164-59.0-8.060-35.0-164.05.016158-2.0
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableTrade

us-gaap:IncreaseDecreaseInAccountsPayableTrade


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-66.011-17.0-66.05381-40.0-143.0-16.075-46.09694-22.0-45.045-20.05.0-47.02542-40.0-68.0-177.089-150.0-97.02002545056-385.0321-128.0134-256.0189-126.062-90.059-34.075-57.0
Percentage of IncreaseDecreaseInAccountsPayableTrade100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value155-79.0120-37.011712-36.0-81.0125-67.087-145.0152-99.069-131.0142-1.030-110.097-45.057-80.0-20.01483-242.023153-73.0-126.056142-76.0-116.07186116-182.07540-65.07.0
Percentage of IncreaseDecreaseInAccruedIncomeTaxesPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInEmployeeRelatedLiabilities

us-gaap:IncreaseDecreaseInEmployeeRelatedLiabilities


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value329333-61.08.058-3.0-123.0565732-108.0277112-137.0275252-102.0-11.04.092-80.052-4.048-118.062-9.057-91.0113-8.02.0-162.0-177.04662-13.0417554-81.0
Percentage of IncreaseDecreaseInEmployeeRelatedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInInterestPayableNet

us-gaap:IncreaseDecreaseInInterestPayableNet


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312016-03-312015-12-312015-03-312014-12-312014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.014-9.029-21.019-5.01347-43.044-35.046-39.027-51.053-62.055-75.070-79.071-80.076-56.053-56.066
Percentage of IncreaseDecreaseInInterestPayableNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value0.0-10.0-7.01.0-50.045-16.00.0-6.012-137.0-15.07.068-75.020390.0-2.0194924-9.01120-23.0242.0
Percentage of IncreaseDecreaseInOtherCurrentLiabilities0.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets

us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets


Increase
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-63.0-68.00.0125-79.0-40.0-39.0148-53.0-29.0-1.0144-71.0-86.016111-55.0-63.09.082-33.0-73.00.0116-84.0-62.0-9.02967-126.026159-139.0349819-102.0-267.0
Percentage of IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements


Incremental
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value01000000.01000000.02000000.01000000.02000000.01000000.03000000.002000000.02000000.02000000.0-1000000.02000000.01000000.01000000.002000000.002000000.01000000.01000000.01000000.02000000.001000000.01000000.01000000.001000000.001000000.002000000.02000000.02000000.002000000.02000000.01000000.001000000.01000000.02000000.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements0.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.00.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

us-gaap:InterestCostsCapitalized

us-gaap:InterestCostsCapitalized


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value7.08.06.07.07.07.07.05.05.05.04.04.010.011111215171717121161418123-14.01822126-17.019
Percentage of InterestCostsCapitalized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsCapitalizedAdjustment

us-gaap:InterestCostsCapitalizedAdjustment


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value20211818181916181816161520192020242826252426
Percentage of InterestCostsCapitalizedAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LateFeeIncomeGeneratedByServicingFinancialAssetsAmount us-gaap:MajorCustomers

us-gaap:LateFeeIncomeGeneratedByServicingFinancialAssetsAmount

fe:OtherNonCustomerRevenue


Late
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value9.06.06.010.08.09.09.0119.09.010.0
Percentage of LateFeeIncomeGeneratedByServicingFinancialAssetsAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic

us-gaap:NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value21246030724-178.038933635017233310621-1061.0301219257
Percentage of NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic

us-gaap:NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value30-6.02.050702.0-28.0-35.0-44.0-845.0281192-1438.095-45.0-52.0
Percentage of NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-4.0-3.0-3.0-23.0-9.0-7.0-7.0-6.0-26.0-16.0-17.0-109.0-14.0-21.0-19.01.0-15.0-12.01912-11.0-40.0-45.0-26.035-53.0-13.0-21.0-26.0-39.0-62.0-40.014-46.0-43.0-45.0
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-4.0-3.0-4.0-23.0-10.0-7.0-7.0-7.0-28.0-18.0-19.0-18.0-30.0-19.0-18.0-18.0-5.0-18.0-18.0-18.0-22.0-31.0-32.0-31.050-42.0-42.0-42.0
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0133.3100.0111.1100.0100.0116.7107.7112.5111.816.5214.390.594.7-1800.033.3150.0-94.7-150.0200.077.571.1119.2142.979.2323.1200.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00.01.00.01.00.00.01.0
Percentage of OtherComprehensiveIncomeLossBeforeTax-0.0-0.0-33.3-0.0-11.1-0.0-0.0-16.7

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00.01.00.03.00.00.01.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax0.00.0100.00.0100.00.00.0100.0

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value4.03.04.02310.07.07.07.028181918301918185.018181822313231-50.042424212475546-33.0474853
Percentage of OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherComprehensiveIncomeLossTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1.0-1.0-1.0-5.0-2.0-3.0-2.0-1.0-6.0-4.0-4.0-53.0-5.0-9.0-7.00.0-5.0-5.07.04.0-5.0-15.0-17.0-10.021-21.0-6.0-8.0-11.0-15.0-24.0-16.0-4.0-24.0-27.0-24.0-97.0-6.0-53.0-1.0-104.014-9.0-7.0
Percentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-1.0-1.0-1.0-5.0-2.0-3.0-2.0-1.0-7.0-4.0-5.0-22.0-11.0-7.0-8.0-6.0-2.0-7.0-7.0-7.0-8.0-12.0-13.0-11.025-16.0-16.0-16.0
Percentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0116.7100.0125.041.5220.077.8114.30.040.0140.0-100.0-175.0160.080.076.5110.0119.076.2266.7200.0

us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherCostAndExpenseOperating


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8759377307498097586067797707397059621195942957114210239539649189528509161057901858102111829488778878841165856914812928102411051033738738673701
Percentage of OtherCostAndExpenseOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherCostAndExpenseOperating us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCredit


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value3.04.0237.07.07.0181918191818
Percentage of OtherCostAndExpenseOperating0.30.53.10.91.20.92.42.71.92.01.91.6

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:OtherOperatingActivitiesCashFlowStatement


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-109.08.0-33.028-152.055131.0-32.010662-7.016424-27.01595.031425951117-7.0735810.0-7.0822.02.031-47.06.014114-36.0
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForProceedsFromOtherInvestingActivities


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8.01.03.0-5.01.02.0-5.02.0-3.02.0-4.01.017-20.012-16.025-27.0-16.0-9.0-3.011-9.00.0-6.01.0-5.0-3.0-6.0-1.0-56.0541.0-9.0418.0-112.010.029220.0-13.0138.0
Percentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:PaymentsForRemovalCosts

us-gaap:PaymentsForRemovalCosts


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value49735943595538654753615742514435443829343144392873338.039211458531108357
Percentage of PaymentsForRemovalCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt


Payments
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value10.03518214160162
Percentage of PaymentsToAcquireAvailableForSaleSecuritiesDebt100.0100.0100.0100.0100.0100.0

us-gaap:PensionAndOtherPostretirementBenefitExpense

us-gaap:PensionAndOtherPostretirementBenefitExpense


Pension
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-03-312010-03-31
Value-74.0-78.0-66.0-28.0-14.0-39.0-16.0-51.0-46.0117.010.0141516-2.0-2.0-12.0-4.07.0-18.0-22.0-20.0-35.0-29.0-40.0-64.0-30.0-33.0-25.0-39.02824
Percentage of PensionAndOtherPostretirementBenefitExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromLongTermLinesOfCredit dei:LegalEntity, us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:ProceedsFromLongTermLinesOfCredit

fe:FEJCPLMEPennTEAndWP, us-gaap:RevolvingCreditFacility, us-gaap:LineOfCredit


Proceeds
Period End2020-11-23
Value950
Percentage of ProceedsFromLongTermLinesOfCredit100.0

us-gaap:ProceedsFromLongTermLinesOfCredit us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:LongtermDebtType

srt:GuarantorSubsidiaries, us-gaap:RevolvingCreditFacility, us-gaap:LineOfCredit


Proceeds
Period End2020-11-23
Value1000
Percentage of ProceedsFromLongTermLinesOfCredit105.3

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-15.00.0-8.0-36.01.0-8.0-3.0-25.0-6.00.0-2.0-19.0-5.0-15.0-39.0-13.0-26.0-41.048-12.0-2.0-9.0-2.00.0-10.0-13.0-14.0-10.0-9.0-48.07.0-23.0-10.0-7.0-25.0-10.0353.0-72.0-4.06.0-2.0-1.0-22.0
Percentage of ProceedsFromPaymentsForOtherFinancingActivities100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt


Proceeds
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value6.02613204149153
Percentage of ProceedsFromSaleOfAvailableForSaleSecuritiesDebt100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForDoubtfulAccounts

us-gaap:ProvisionForDoubtfulAccounts


Provision
Period End2020-09-302020-06-302020-03-31
Value336019
Percentage of ProvisionForDoubtfulAccounts100.0100.0100.0

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity

us-gaap:PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity


Public
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1313121111129.0131311121110.08.09.08.09.0119.08.09.0-10.019161414147.0174.04.0
Percentage of PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilitiesApprovedDebtCapitalStructurePercentage dei:LegalEntity

us-gaap:PublicUtilitiesApprovedDebtCapitalStructurePercentage

fe:JcpAndL


Public
Period End2020-11-01
Value48.56
Percentage of PublicUtilitiesApprovedDebtCapitalStructurePercentage100.0

us-gaap:PublicUtilitiesApprovedEquityCapitalStructurePercentage dei:LegalEntity

us-gaap:PublicUtilitiesApprovedEquityCapitalStructurePercentage

fe:JcpAndL


Public
Period End2020-11-01
Value51.44
Percentage of PublicUtilitiesApprovedEquityCapitalStructurePercentage100.0

us-gaap:PublicUtilitiesApprovedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

us-gaap:PublicUtilitiesApprovedRateIncreaseDecreaseAmount

fe:JcpAndL, stpr:NJ, fe:JCPLReliabilityPlus, fe:NewJerseyBoardofPublicUtilities


Public
Period End2020-11-012019-04-232018-12-17
Value959797
Percentage of PublicUtilitiesApprovedRateIncreaseDecreaseAmount100.0100.0100.0

us-gaap:PublicUtilitiesApprovedReturnOnEquityPercentage dei:LegalEntity

us-gaap:PublicUtilitiesApprovedReturnOnEquityPercentage

fe:JcpAndL


Public
Period End2020-11-01
Value9.6
Percentage of PublicUtilitiesApprovedReturnOnEquityPercentage100.0

us-gaap:PublicUtilitiesApprovedReturnOnEquityPercentage dei:LegalEntity, us-gaap:StatementBusinessSegments, us-gaap:SubsequentEventType

fe:JcpAndL, fe:RegulatedTransmission, us-gaap:SubsequentEvent


Public
Period End2021-02-02
Value10.2
Percentage of PublicUtilitiesApprovedReturnOnEquityPercentage0.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount

fe:Pe, stpr:MD


Public
Period End2020-09-01
Value148
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount100.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:ExpandedNetEnergyCost, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-08-282019-08-212018-08-31
Value-55.0-6.1100
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.00.00.0

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:ModernizationAndImprovementProgramForCoalFiredBoilers, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-08-28
Value5.0
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementBusinessSegments

fe:JcpAndL, stpr:NJ, fe:EnergyEfficiencyAndPeakDemandReduction, fe:NewJerseyBoardofPublicUtilities, fe:RegulatedDistribution


Public
Period End2020-09-25
Value230
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType

fe:CEIOEandTE, stpr:OH, fe:DecouplingRider, fe:PublicUtilitiesCommissionOfOhio, us-gaap:SubsequentEvent


Public
Period End2020-11-02
Value113
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

fe:Pe, stpr:MD, fe:DepreciationExpenseStudy, fe:MarylandOfficeOfPeoplesCounsel, us-gaap:SubsequentEvent


Public
Period End2021-01-29
Value-10.8
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

fe:Pe, stpr:MD, fe:DepreciationExpenseStudy, fe:MarylandPublicServiceCommission, us-gaap:SubsequentEvent


Public
Period End2021-01-29
Value-9.6
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:StatementBusinessSegments

fe:JcpAndL, stpr:NJ, fe:AdvancedMeteringInfrastructure, fe:RegulatedDistribution


Public
Period End2020-08-27
Value732
Percentage of PublicUtilitiesRequestedRateIncreaseDecreaseAmount0.0

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreasePercentage dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

us-gaap:PublicUtilitiesRequestedRateIncreaseDecreasePercentage

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, stpr:WV, fe:ExpandedNetEnergyCost, fe:PublicServiceCommissionofWestVirginia


Public
Period End2020-08-282019-08-21
Value-4.1-0.004
Percentage of PublicUtilitiesRequestedRateIncreaseDecreasePercentage100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax


Reclassification
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value3.03.0237.07.06.0161717482331332829323840556256
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Reclassification
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value3.04.0237.07.07.0181918191818181818313231424242
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax100.0133.3100.0100.0100.0116.7112.5111.8105.939.678.358.154.564.362.196.984.277.576.467.775.0

us-gaap:AccumulatedGainLossNetCashFlowHedgeParent


Reclassification
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.0-1.00.00.00.0-1.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax0.0-33.30.00.00.0-16.7

us-gaap:RepaymentsOfShortTermDebt

us-gaap:RepaymentsOfShortTermDebt


Repayments
Period End2020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-03-31
Value-185.06352500.00.00.00.0200-275.00.00.0910.00.00.0-178.07027623190.00.00.00.00.00.00.00.00.0656-170.0214207295
Percentage of RepaymentsOfShortTermDebt100.0100.0100.00.00.00.00.0100.0100.00.00.0100.00.00.00.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodSharesEmployeeBenefitPlan us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesEmployeeBenefitPlan

us-gaap:CommonStock


Stock
Period End2020-09-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1.01.01.01.01.01.01.02.0
Percentage of StockIssuedDuringPeriodSharesEmployeeBenefitPlan100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeBenefitPlan

us-gaap:StockIssuedDuringPeriodValueEmployeeBenefitPlan


Stock
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1722-15.020211.021196.0
Percentage of StockIssuedDuringPeriodValueEmployeeBenefitPlan100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeBenefitPlan us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stock
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1722-15.020211.021195.0
Percentage of StockIssuedDuringPeriodValueEmployeeBenefitPlan100.0100.0100.0100.0100.0100.0100.0100.083.3

us-gaap:UtilitiesOperatingExpensePurchasedPower

us-gaap:UtilitiesOperatingExpensePurchasedPower


Utilities
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value766613694798611781876697820774
Percentage of UtilitiesOperatingExpensePurchasedPower100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UtilitiesOperatingExpenseTaxes

us-gaap:UtilitiesOperatingExpenseTaxes


Utilities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value254272253267251257239261247252245259266253253271256265241280231236242269224239228271231242241265224257232272230269242
Percentage of UtilitiesOperatingExpenseTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale

fe:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale


Accumulated
Period End2020-12-312019-12-31
Value1196511427
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale100.0100.0

fe:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Accumulated
Period End2020-12-312019-12-31
Value88008540
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale73.574.7

fe:RegulatedTransmission


Accumulated
Period End2020-12-312019-12-31
Value26092383
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale21.820.9

us-gaap:CorporateAndOther


Accumulated
Period End2020-12-312019-12-31
Value556504
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipmentIncludingDisposalGroupIncludingDiscontinuedOperationsAssetsHeldForSale4.64.4

fe:AdversePowerContractLiability

fe:AdversePowerContractLiability


Adverse
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value30313138496679858999113124130143152157162174181194197205203213217222237255290467484465506550559458469665649466
Percentage of AdversePowerContractLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:AllowanceForLoanAndLossDeferredRecoveryOfBadDebts

fe:AllowanceForLoanAndLossDeferredRecoveryOfBadDebts


Allowance
Period End2020-12-312020-09-302020-06-302019-12-312018-12-31
Value10354352524
Percentage of AllowanceForLoanAndLossDeferredRecoveryOfBadDebts100.0100.0100.0100.0100.0

fe:AmountOfImpairmentToCarryingAmountOfRegulatoryAssetsNet dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:AmountOfImpairmentToCarryingAmountOfRegulatoryAssetsNet

fe:CEIOEandTE, stpr:OH, fe:RiderCSR, fe:PublicUtilitiesCommissionOfOhio


Amount
Period End2020-12-31
Value84
Percentage of AmountOfImpairmentToCarryingAmountOfRegulatoryAssetsNet100.0

fe:AssetAcquisitionRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAssets dei:LegalEntity, fe:AssetAcquisition, us-gaap:StatementGeographical, us-gaap:StatementBusinessSegments

fe:AssetAcquisitionRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAssets

fe:JcpAndL, fe:YardsCreekEnergyLLCHydroGenerationFacility, stpr:NJ, fe:RegulatedDistribution


Asset
Period End2020-12-312020-09-30
Value4544
Percentage of AssetAcquisitionRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAssets100.0100.0

fe:CashandCashEquivalentsHeldforSaleFairValueDisclosure

fe:CashandCashEquivalentsHeldforSaleFairValueDisclosure


Cashand
Period End2020-09-302020-06-302020-03-312019-12-31
Value746750751747
Percentage of CashandCashEquivalentsHeldforSaleFairValueDisclosure100.0100.0100.0100.0

fe:CompanyPostedCollateralRelatedToNetLiabilityPositions

fe:CompanyPostedCollateralRelatedToNetLiabilityPositions


Company
Period End2020-12-312020-09-302011-06-302011-03-31
Value201.081162
Percentage of CompanyPostedCollateralRelatedToNetLiabilityPositions100.0100.0100.0100.0

fe:DeactivatedPowerPlantsCapacity us-gaap:StatementBusinessSegments, us-gaap:StatementScenario

fe:DeactivatedPowerPlantsCapacity

fe:CompetitiveEnergyServices, us-gaap:ScenarioForecast


Deactivated
Period End2020-12-31
Value856.0
Percentage of DeactivatedPowerPlantsCapacity100.0

fe:DebtInstrumentUnamortizedMergerFairValueAdjustments

fe:DebtInstrumentUnamortizedMergerFairValueAdjustments


Debt
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value7.08.010.0-14.0-6.05.02144103
Percentage of DebtInstrumentUnamortizedMergerFairValueAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DebtSecuritiesHeldforsale

fe:DebtSecuritiesHeldforsale


Debt
Period End2020-09-302020-06-302020-03-312019-12-31
Value135132124135
Percentage of DebtSecuritiesHeldforsale100.0100.0100.0100.0

fe:DeferredChargesandOtherAssetsNoncurrent

fe:DeferredChargesandOtherAssetsNoncurrent


Deferred
Period End2020-09-302020-06-302020-03-312019-12-31
Value6412650866446756
Percentage of DeferredChargesandOtherAssetsNoncurrent100.0100.0100.0100.0

fe:DeferredIncomeTaxLiabilitiesNetNoncurrent

fe:DeferredIncomeTaxLiabilitiesNetNoncurrent


Deferred
Period End2020-12-312019-12-312018-12-31
Value309528492502
Percentage of DeferredIncomeTaxLiabilitiesNetNoncurrent100.0100.0100.0

fe:DeferredTaxAssetsLiabilitiesNetAssetRetirementObligationLiability

fe:DeferredTaxAssetsLiabilitiesNetAssetRetirementObligationLiability


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value28226215453669731641651
Percentage of DeferredTaxAssetsLiabilitiesNetAssetRetirementObligationLiability100.0100.0100.0100.0100.0100.0100.0100.0

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardValuationReserve

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardValuationReserve


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value496441-394.0-580.0-438.0-192.0-174.0-142.0-102.0-34.0
Percentage of DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardValuationReserve100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardsAndTaxCredits

fe:DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardsAndTaxCredits


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value1995836899146722511965193215991199612
Percentage of DeferredTaxAssetsLiabilitiesNetNonCurrentLossCarryForwardsAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpirationNetOfTax

fe:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpirationNetOfTax


Deferred
Period End2020-12-31
Value540
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpirationNetOfTax100.0

fe:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpirationNetOfTax

fe:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpirationNetOfTax


Deferred
Period End2020-12-31
Value1400
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpirationNetOfTax100.0

fe:DefinedBenefitPlanMarktoMarketAdjustmentNet

fe:DefinedBenefitPlanMarktoMarketAdjustmentNet


Defined
Period End2020-12-312020-03-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value54423676145141147242835-256.0609
Percentage of DefinedBenefitPlanMarktoMarketAdjustmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:DefinedBenefitPlanMarktoMarketAdjustmentNet dei:LegalEntity

fe:ATSIMAITAndTrAIL


Defined
Period End2020-12-31
Value21
Percentage of DefinedBenefitPlanMarktoMarketAdjustmentNet38.9

fe:DisposalGroupIncludingDiscontinuedOperationInvestments

fe:DisposalGroupIncludingDiscontinuedOperationInvestments


Disposal
Period End2020-09-302020-06-302020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value8818828758820.00.00.00.01875
Percentage of DisposalGroupIncludingDiscontinuedOperationInvestments100.0100.0100.0100.00.00.00.00.0100.0

fe:EnvironmentalLiabilitiesFormerGasFacilities fe:LossContingenciesByClaims

fe:EnvironmentalLiabilitiesFormerGasFacilities

fe:RegulationOfWasteDisposal


Environmental
Period End2020-12-312020-09-302019-12-31
Value676877
Percentage of EnvironmentalLiabilitiesFormerGasFacilities100.0100.0100.0

fe:ExpendituresForCostRecoveryProgram dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding

fe:ExpendituresForCostRecoveryProgram

fe:Pe, stpr:MD, fe:A20212023EmPOWERProgramCycle


Expenditures
Period End2020-12-18
Value148
Percentage of ExpendituresForCostRecoveryProgram100.0

fe:FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

fe:FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue

fe:Ftrs, us-gaap:FairValueInputsLevel3


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-31
Value3.07.05.0-1.03.03.02.0-1.09.09.00.01.03.03.02.0-4.01.06.09.0-6.0-5.03.010.02.0252421-1.0-8.0-11.0-2.0-3.0-1.0-22.00.0
Percentage of FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

fe:FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:ValuationTechnique

fe:Ftrs, us-gaap:FairValueInputsLevel3, fe:Model


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value3.07.05.0-1.03.03.02.0-1.09.09.00.01.03.03.02.0-4.01.06.09.0-6.0-5.03.010.02.0252421-1.0-8.0-11.0-2.0-3.0-1.0
Percentage of FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityNetValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:FairValueOfAssetsLiabilitiesNet us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

fe:FairValueOfAssetsLiabilitiesNet

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value1736262118168629706
Percentage of FairValueOfAssetsLiabilitiesNet100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value3171190120712001195722
Percentage of FairValueOfAssetsLiabilitiesNet18.3454.21022.9714.3190.0102.3

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value3.07.05.0-7.0-13.0-35.0
Percentage of FairValueOfAssetsLiabilitiesNet0.22.74.2-4.2-2.1-5.0

fe:FairValueOfAssetsLiabilitiesNet us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Fair
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value205614591330136118111393
Percentage of FairValueOfAssetsLiabilitiesNet118.4556.91127.1810.1287.9197.3

fe:FinancingLeaseRightofUseAssetAccumulatedAmortization

fe:FinancingLeaseRightofUseAssetAccumulatedAmortization


Financing
Period End2020-12-312019-12-31
Value9690
Percentage of FinancingLeaseRightofUseAssetAccumulatedAmortization100.0100.0

fe:InvestmentOwnershipPercentagePledgedAsCollateral dei:LegalEntity, fe:BusinessUnits, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

fe:InvestmentOwnershipPercentagePledgedAsCollateral

fe:GlobalHolding, fe:SignalPeakGlobalRailAndAffiliates, fe:SeniorSecuredTermLoan, us-gaap:SeniorLoans


Investment
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value69.9969.990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.69990.6999
Percentage of InvestmentOwnershipPercentagePledgedAsCollateral100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:InvestmentOwnershipPercentagePledgedAsCollateral dei:LegalEntity, fe:BusinessUnits, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

fe:Fev, fe:SignalPeak, fe:GlobalHolding, fe:SeniorSecuredTermLoan, us-gaap:SeniorLoans


Investment
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value33.330.33330.33330.33330.33330.33330.33330.33330.3333
Percentage of InvestmentOwnershipPercentagePledgedAsCollateral47.647.647.647.647.647.647.647.647.6

fe:WmbMarketingVenturesLlc, fe:SignalPeak, fe:GlobalHolding, fe:SeniorSecuredTermLoan, us-gaap:SeniorLoans


Investment
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value33.330.333330.33330.33330.33330.33330.33330.33330.3333
Percentage of InvestmentOwnershipPercentagePledgedAsCollateral47.647.647.647.647.647.647.647.647.6

fe:InvestmentsExcludesReceivablesPayablesDeferredTaxesAndAccruedIncome

fe:InvestmentsExcludesReceivablesPayablesDeferredTaxesAndAccruedIncome


Investments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value1.02.0-19.0-18.0-16.0-15.0-15.0-12.04.0-33.0-12.0-15.0-8.0-13.0-18.0-14.0-3.0-8.07.0-6.07.0-4.0-6.0-32.040-45.0-36.09.010.0134.0-10.011043-7.02.0-52.0-29.06.0-7.0
Percentage of InvestmentsExcludesReceivablesPayablesDeferredTaxesAndAccruedIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:InvestmentsFinancialInstrumentsReceivablesPayablesTaxesAndAccruedIncome us-gaap:RetirementPlanType

fe:InvestmentsFinancialInstrumentsReceivablesPayablesTaxesAndAccruedIncome

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Investments
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-10.01.0-2.0-2.0-4.0
Percentage of InvestmentsFinancialInstrumentsReceivablesPayablesTaxesAndAccruedIncome100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Investments
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value11617668-10.016
Percentage of InvestmentsFinancialInstrumentsReceivablesPayablesTaxesAndAccruedIncome-1160.017600.0-3400.0500.0-400.0

fe:InvestmentsNotRequiredToBeDisclosed

fe:InvestmentsNotRequiredToBeDisclosed


Investments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value322301297288299283275257253254255252255255254269266276273271255623636642626633636635636646640640644709716689693312345345259264
Percentage of InvestmentsNotRequiredToBeDisclosed100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:LeaseObligations

fe:LeaseObligations


Lease
Period End2020-12-312019-12-312019-09-302019-06-30
Value350333309294
Percentage of LeaseObligations100.0100.0100.0100.0

fe:LeasedAsset

fe:LeasedAsset


Leased
Period End2020-12-312019-12-31
Value322304
Percentage of LeasedAsset100.0100.0

fe:LesseeLeaseLiability

fe:LesseeLeaseLiability


Lessee
Period End2020-12-312019-12-31
Value350333
Percentage of LesseeLeaseLiability100.0100.0

fe:LesseeLeaseLiabilityPaymentsDue

fe:LesseeLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-312019-12-31
Value427419
Percentage of LesseeLeaseLiabilityPaymentsDue100.0100.0

fe:LesseeLeaseLiabilityPaymentsDueAfterYearFive

fe:LesseeLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-12-312019-12-31
Value159170
Percentage of LesseeLeaseLiabilityPaymentsDueAfterYearFive100.0100.0

fe:LesseeLeaseLiabilityPaymentsDueYearFive

fe:LesseeLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-312019-12-31
Value4033
Percentage of LesseeLeaseLiabilityPaymentsDueYearFive100.0100.0

fe:LesseeLeaseLiabilityPaymentsDueYearFour

fe:LesseeLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-312019-12-31
Value4244
Percentage of LesseeLeaseLiabilityPaymentsDueYearFour100.0100.0

fe:LesseeLeaseLiabilityPaymentsDueYearThree

fe:LesseeLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-312019-12-31
Value5455
Percentage of LesseeLeaseLiabilityPaymentsDueYearThree100.0100.0

fe:LesseeLeaseLiabilityPaymentsDueYearTwo

fe:LesseeLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-312019-12-31
Value6457
Percentage of LesseeLeaseLiabilityPaymentsDueYearTwo100.0100.0

fe:LesseeLeaseLiabilityPaymentsImputedInterest

fe:LesseeLeaseLiabilityPaymentsImputedInterest


Lessee
Period End2020-12-312019-12-31
Value7786
Percentage of LesseeLeaseLiabilityPaymentsImputedInterest100.0100.0

fe:LesseeLeaseLiabilityPaymentsNextTwelveMonths

fe:LesseeLeaseLiabilityPaymentsNextTwelveMonths


Lessee
Period End2020-12-312019-12-31
Value6860
Percentage of LesseeLeaseLiabilityPaymentsNextTwelveMonths100.0100.0

fe:LesseeOperatingLeaseLeaseNotyetCommencedAmount

fe:LesseeOperatingLeaseLeaseNotyetCommencedAmount


Lessee
Period End2020-12-312019-12-31
Value1413
Percentage of LesseeOperatingLeaseLeaseNotyetCommencedAmount100.0100.0

fe:LesseeOperatingLeaseResidualValueGuaranteePotentialLoss

fe:LesseeOperatingLeaseResidualValueGuaranteePotentialLoss


Lessee
Period End2020-12-312019-12-31
Value1615
Percentage of LesseeOperatingLeaseResidualValueGuaranteePotentialLoss100.0100.0

fe:NetPlantExcludingConstructionWorkInProgress

fe:NetPlantExcludingConstructionWorkInProgress


Net
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value317163120630976305493034029782294332906728676281172787127450278532814327930272072803635439350723495034792342833413433484333343262432336312273094830922308613092530610293222883128501282832754727975268231827116429
Percentage of NetPlantExcludingConstructionWorkInProgress100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale

fe:NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale


Net
Period End2020-12-312019-12-31
Value3176130340
Percentage of NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale100.0100.0

fe:NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Net
Period End2020-12-312019-12-31
Value2097520195
Percentage of NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale66.066.6

fe:RegulatedTransmission


Net
Period End2020-12-312019-12-31
Value103039640
Percentage of NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale32.431.8

us-gaap:CorporateAndOther


Net
Period End2020-12-312019-12-31
Value483505
Percentage of NetPlantExcludingConstructionWorkInProgressIncludingAssetsHeldForSale1.51.7

fe:NetRegulatoryAssetsInvestmentReturnToBeRecovered

fe:NetRegulatoryAssetsInvestmentReturnToBeRecovered


Net
Period End2020-12-312019-12-312018-12-31
Value195228290
Percentage of NetRegulatoryAssetsInvestmentReturnToBeRecovered100.0100.0100.0

fe:NuclearFuelDisposalTrust

fe:NuclearFuelDisposalTrust


Nuclear
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312011-09-302011-06-302010-12-31
Value283281278275270271265259256253252251251218212208
Percentage of NuclearFuelDisposalTrust100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:OperatingLeaseRightofUseAssetAccumulatedAmortization

fe:OperatingLeaseRightofUseAssetAccumulatedAmortization


Operating
Period End2020-12-312019-12-31
Value5123
Percentage of OperatingLeaseRightofUseAssetAccumulatedAmortization100.0100.0

fe:OperatingLossCarryforwardsExpectedToUtilizedNetofTax

fe:OperatingLossCarryforwardsExpectedToUtilizedNetofTax


Operating
Period End2020-12-31
Value155
Percentage of OperatingLossCarryforwardsExpectedToUtilizedNetofTax100.0

fe:PlantCapacity dei:LegalEntity, us-gaap:StatementBusinessSegments

fe:PlantCapacity

fe:Ovec, fe:OtherBusinessOperations


Plant
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value67.067.067.067.067.067.067.070.070.0
Percentage of PlantCapacity100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:PlantCapacity us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Plant
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-10-09
Value3790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03790.03780.03780.0
Percentage of PlantCapacity5656.75656.75656.75656.75656.75656.75656.75414.35414.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

fe:PrepaidTaxesandOther

fe:PrepaidTaxesandOther


Prepaid
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value157157175219256
Percentage of PrepaidTaxesandOther100.0100.0100.0100.0100.0

fe:PretaxNetOperatingLossCarryforwardsExpectedToUtilized

fe:PretaxNetOperatingLossCarryforwardsExpectedToUtilized


Pretax
Period End2020-12-31
Value3800
Percentage of PretaxNetOperatingLossCarryforwardsExpectedToUtilized100.0

fe:PropertyPlantAndEquipmentExcludingConstructionInProgress

fe:PropertyPlantAndEquipmentExcludingConstructionInProgress


Property
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-31
Value436544317742794421844176741016405724002839469385853833437717397784422943929429764376750889503675037149952492004886247992474844666446133447824422844089438884374843210417564116740122
Percentage of PropertyPlantAndEquipmentExcludingConstructionInProgress100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale

fe:PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale


Property
Period End2020-12-312019-12-31
Value3333931650
Percentage of PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale100.0100.0

fe:PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale us-gaap:StatementBusinessSegments

fe:RegulatedDistribution


Property
Period End2020-12-312019-12-31
Value2181620939
Percentage of PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale65.466.2

fe:RegulatedTransmission


Property
Period End2020-12-312019-12-31
Value1097410166
Percentage of PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale32.932.1

us-gaap:CorporateAndOther


Property
Period End2020-12-312019-12-31
Value549545
Percentage of PropertyPlantAndEquipmentNetIncludingAssetsHeldForSale1.61.7

fe:PublicUtilityCapacityShortfall dei:LegalEntity, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, us-gaap:StatementGeographical, us-gaap:StatementScenario

fe:PublicUtilityCapacityShortfall

fe:MonogahelaPowerCompany, fe:AcceleratedRecoveryCostsForModernizingandImprovingCoalFiredBoilers, fe:PublicServiceCommissionofWestVirginia, stpr:WV, us-gaap:ScenarioForecast


Public
Period End2020-12-31
Value700.0
Percentage of PublicUtilityCapacityShortfall100.0

fe:MonogahelaPowerCompany, fe:IntegratedResourcePlan, fe:PublicServiceCommissionofWestVirginia, stpr:WV, us-gaap:ScenarioForecast


Public
Period End2027-12-31
Value850.0
Percentage of PublicUtilityCapacityShortfall0.0

fe:MonogahelaPowerCompanyandThePotomacEdisonCompany, fe:AcceleratedRecoveryCostsForModernizingandImprovingCoalFiredBoilers, fe:PublicServiceCommissionofWestVirginia, stpr:WV, us-gaap:ScenarioForecast


Public
Period End2020-12-31
Value700.0
Percentage of PublicUtilityCapacityShortfall100.0

fe:MonongahelaPowerCompany, fe:AcceleratedRecoveryCostsForModernizingandImprovingCoalFiredBoilers, fe:PublicServiceCommissionofWestVirginia, stpr:WV, us-gaap:ScenarioForecast


Public
Period End2020-12-31
Value700.0
Percentage of PublicUtilityCapacityShortfall100.0

fe:MonongahelaPowerCompany, fe:IntegratedResourcePlan, fe:PublicServiceCommissionofWestVirginia, stpr:WV, us-gaap:ScenarioForecast


Public
Period End2027-12-31
Value850.0
Percentage of PublicUtilityCapacityShortfall0.0

fe:RatioofInterestCoverage us-gaap:CreditFacility, us-gaap:Range, us-gaap:ShortTermDebtType, us-gaap:StatementScenario

fe:RatioofInterestCoverage

us-gaap:RevolvingCreditFacility, us-gaap:Minimum, us-gaap:LineOfCredit, us-gaap:ScenarioForecast


Ratioof
Period End2021-12-312019-12-312018-12-312017-12-31
Value2.52.252.01.75
Percentage of RatioofInterestCoverage100.0100.0100.0100.0

fe:ReductioninPowerPlantsCarbonPollutionPercentage

fe:ReductioninPowerPlantsCarbonPollutionPercentage


Reductionin
Period End2020-09-30
Value62.0
Percentage of ReductioninPowerPlantsCarbonPollutionPercentage100.0

fe:RegulatoryAssetRecoveryAssessmentsLostDistributionRevenue dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

fe:RegulatoryAssetRecoveryAssessmentsLostDistributionRevenue

fe:CEIOEandTE, stpr:OH, fe:RiderCSR, fe:PublicUtilitiesCommissionOfOhio


Regulatory
Period End2020-12-31
Value77
Percentage of RegulatoryAssetRecoveryAssessmentsLostDistributionRevenue100.0

fe:RemainingAmountsOfRegulatoryAssetsTorWhichAreBeingSoughtForRecoveryInAFormulaRateAmendment

fe:RemainingAmountsOfRegulatoryAssetsTorWhichAreBeingSoughtForRecoveryInAFormulaRateAmendment


Remaining
Period End2020-12-312019-12-31
Value7973
Percentage of RemainingAmountsOfRegulatoryAssetsTorWhichAreBeingSoughtForRecoveryInAFormulaRateAmendment100.0100.0

fe:RemainingAmountsofRegulatoryAssetsforwhichRecoveryisBasedonPriorPrecedentorRateMakingwithoutaSpecificOrder

fe:RemainingAmountsofRegulatoryAssetsforwhichRecoveryisBasedonPriorPrecedentorRateMakingwithoutaSpecificOrder


Remaining
Period End2020-12-312019-12-31
Value117111
Percentage of RemainingAmountsofRegulatoryAssetsforwhichRecoveryisBasedonPriorPrecedentorRateMakingwithoutaSpecificOrder100.0100.0

fe:ServiceArea us-gaap:StatementBusinessSegments

fe:ServiceArea

fe:RegulatedTransmission


Service
Period End2020-12-312019-12-312018-12-31
Value24500.024500.025000.0
Percentage of ServiceArea100.0100.0100.0

fe:UnrecognizedTaxBenefitsPortionExpectedToBeResolvedInNextFiscalYear

fe:UnrecognizedTaxBenefitsPortionExpectedToBeResolvedInNextFiscalYear


Unrecognized
Period End2020-12-312020-09-302019-12-31
Value575759
Percentage of UnrecognizedTaxBenefitsPortionExpectedToBeResolvedInNextFiscalYear100.0100.0100.0

fe:UnrecognizedTaxBenefitsthatWouldImpactEffectiveTaxRateFutureYears

fe:UnrecognizedTaxBenefitsthatWouldImpactEffectiveTaxRateFutureYears


Unrecognized
Period End2020-12-312019-12-31
Value121151
Percentage of UnrecognizedTaxBenefitsthatWouldImpactEffectiveTaxRateFutureYears100.0100.0

fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyOne us-gaap:ConsolidatedEntities, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyOne

us-gaap:VariableInterestEntityNotPrimaryBeneficiary, fe:PathWv


Variable
Period End2020-12-31
Value100.0
Percentage of VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyOne100.0

fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyTwo us-gaap:ConsolidatedEntities, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

fe:VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyTwo

us-gaap:VariableInterestEntityNotPrimaryBeneficiary, fe:PathWv


Variable
Period End2020-12-31
Value50.0
Percentage of VariableInterestEntitiesPercentageOfHighVoltageTransmissionLineProjectOwnedByVariableInterestEntityOneInJointVenturePartyTwo100.0

us-gaap:AccountsReceivableGrossCurrent us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:AccountsReceivableGrossCurrent

fe:Customer


Accounts
Period End2020-12-312020-09-302020-06-302020-03-312019-12-31
Value13671220110710531137
Percentage of AccountsReceivableGrossCurrent100.0100.0100.0100.0100.0

us-gaap:AccrualForEnvironmentalLossContingencies fe:LossContingenciesByClaims

us-gaap:AccrualForEnvironmentalLossContingencies

fe:RegulationOfWasteDisposal


Accrual
Period End2020-12-312020-09-302019-12-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value107104109124123122106106103133104
Percentage of AccrualForEnvironmentalLossContingencies100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccruedEmployeeBenefitsCurrent

us-gaap:AccruedEmployeeBenefitsCurrent


Accrued
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value349339267252258268231253318300264254336337293307363365341309334345323249329277283232351289298240331313288258384350331312315293
Percentage of AccruedEmployeeBenefitsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivable

us-gaap:AllowanceForDoubtfulAccountsReceivable


Allowance
Period End2020-09-302020-06-302020-03-312019-12-312018-12-31
Value10887444650
Percentage of AllowanceForDoubtfulAccountsReceivable100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivable us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

fe:Customer


Allowance
Period End2020-12-312019-12-312018-12-312017-12-31
Value164465049
Percentage of AllowanceForDoubtfulAccountsReceivable0.0100.0100.00.0

fe:OtherReceivables


Allowance
Period End2020-12-312019-12-312018-12-312017-12-31
Value26212.01.0
Percentage of AllowanceForDoubtfulAccountsReceivable0.045.74.00.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

fe:Customer


Allowance
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value1641088744464646485049495051525252536163646964626059635955524140414043363537373536
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

fe:OtherReceivables


Allowance
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value26242626217.03.01.02.02.02.01.01.01.01.01.01.03.03.05.05.05.05.05.05.05.03.03.03.03.03.03.04.02.02.08.03.09.08.08.0
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent15.922.229.959.145.715.26.52.14.04.14.12.02.01.91.91.91.94.94.87.87.27.88.18.38.57.95.15.55.87.37.57.310.04.75.622.98.124.322.922.2

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent us-gaap:RelatedPartyTransactionsByRelatedParty

srt:AffiliatedEntity


Allowance
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.01063945937928920
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent0.02310.92054.32037.01933.31840.0

us-gaap:AmountOfImpairmentToCarryingAmountOfRegulatoryAssets dei:LegalEntity, us-gaap:StatementGeographical, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency

us-gaap:AmountOfImpairmentToCarryingAmountOfRegulatoryAssets

fe:CEIOEandTE, stpr:OH, fe:RiderCSR, fe:PublicUtilitiesCommissionOfOhio


Amount
Period End2020-12-31
Value108
Percentage of AmountOfImpairmentToCarryingAmountOfRegulatoryAssets100.0

us-gaap:AssetRetirementObligation

us-gaap:AssetRetirementObligation


Asset
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312016-09-302016-06-302015-12-312014-12-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value159856812630589580251514821459144814101387167818341795176715991497140714251347
Percentage of AssetRetirementObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetRetirementObligationsNoncurrent

us-gaap:AssetRetirementObligationsNoncurrent


Asset
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value159173170168165844833822812630589580251515501526150514821459144814271410142914111390138717551730170416781834179517671599157415481522149714731459144314071425
Percentage of AssetRetirementObligationsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperation us-gaap:DisposalGroupClassification, us-gaap:PublicUtility, us-gaap:StatementBusinessSegments

us-gaap:AssetsOfDisposalGroupIncludingDiscontinuedOperation

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, fe:ThreeMileIslandUnit2, fe:RegulatedDistribution


Assets
Period End2020-12-312020-09-302020-06-302020-03-312019-12-31
Value882881882875882
Percentage of AssetsOfDisposalGroupIncludingDiscontinuedOperation100.0100.0100.0100.0100.0

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, fe:YardCreekGeneratingFacility, fe:RegulatedDistribution


Assets
Period End2020-12-312020-09-302020-06-30
Value454444
Percentage of AssetsOfDisposalGroupIncludingDiscontinuedOperation5.15.05.0

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax

us-gaap:DebtSecurities


Available
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value7.0118.08.09.0272210.02.02.02.05.011
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

us-gaap:DebtSecurities


Available
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value6.08.08.016111415162823272217
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis

us-gaap:DebtSecurities


Available
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value275406407405403736730723714712783783774
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtSecurities us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:DebtSecurities


Available
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value276409407397401749737717688691758766768
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalLeaseObligations

us-gaap:CapitalLeaseObligations


Capital
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value456073911041321601881761085413
Percentage of CapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalLeasedAssetsGross

us-gaap:CapitalLeasedAssetsGross


Capital
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value153163173238244253281
Percentage of CapitalLeasedAssetsGross100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizationLongtermDebtAndEquity

us-gaap:CapitalizationLongtermDebtAndEquity


Capitalization
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value29368293912912327635265932669426322257462456523481241602411525040274952690223901244333003529755313423161431721311013148031598312353110029409285262783828252288142827229076286712886629015288382944121092
Percentage of CapitalizationLongtermDebtAndEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:CashAndCashEquivalentsFairValueDisclosure


Cash
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value9.075375375375120
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockValueOutstanding

us-gaap:CommonStockValueOutstanding


Common
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value545454545454535351514848444444444443424242424242424242424242424242424242424242423131
Percentage of CommonStockValueOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentCarryingAmount us-gaap:ConsolidatedEntities, us-gaap:CreditFacility, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentCarryingAmount

srt:GuarantorSubsidiaries, us-gaap:RevolvingCreditFacility, us-gaap:LineOfCredit


Debt
Period End2020-11-23
Value1000
Percentage of DebtInstrumentCarryingAmount100.0

srt:ParentCompany, us-gaap:RevolvingCreditFacility, us-gaap:LineOfCredit


Debt
Period End2020-11-23
Value1200
Percentage of DebtInstrumentCarryingAmount120.0

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet


Debt
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value3433394225188.0-9.0-45.0-64.0
Percentage of DebtInstrumentUnamortizedDiscountPremiumNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent us-gaap:DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensation

us-gaap:DeferredCompensationLiabilityClassifiedNoncurrent

fe:DeferredCompensationPlanDirectors


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value7000000.09000000.09000000.08000000.07000000.09000000.08000000.07000000.06000000.0
Percentage of DeferredCompensationLiabilityClassifiedNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent us-gaap:AwardType

us-gaap:DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent

fe:PerformancebasedRestrictedStockUnits


Deferred
Period End2020-12-312019-12-31
Value1646
Percentage of DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent100.0100.0

us-gaap:DeferredCostsAndOtherAssets

us-gaap:DeferredCostsAndOtherAssets


Deferred
Period End2020-12-312019-12-31
Value68066756
Percentage of DeferredCostsAndOtherAssets100.0100.0

us-gaap:DeferredFinanceCostsGross

us-gaap:DeferredFinanceCostsGross


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value118103951138793
Percentage of DeferredFinanceCostsGross100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration


Deferred
Period End2020-12-31
Value12400
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsNotSubjectToExpiration100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration

us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration


Deferred
Period End2020-12-31
Value6800
Percentage of DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration100.0

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsOther


Deferred
Period End2020-12-312019-12-312018-12-31
Value280242208
Percentage of DeferredTaxAssetsOther100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits


Deferred
Period End2020-12-312019-12-312018-12-31
Value769698629
Percentage of DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value165154170177269239
Percentage of DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesParentsBasisInDiscontinuedOperation

us-gaap:DeferredTaxLiabilitiesParentsBasisInDiscontinuedOperation


Deferred
Period End2020-12-312019-12-312018-12-31
Value539650374737
Percentage of DeferredTaxLiabilitiesParentsBasisInDiscontinuedOperation100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities

us-gaap:DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities


Deferred
Period End2020-12-312019-12-312018-12-31
Value440445414
Percentage of DeferredTaxLiabilitiesRegulatoryAssetsAndLiabilities100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1137610439895195838913
Percentage of DefinedBenefitPlanAccumulatedBenefitObligation100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-39.0-85.0-121.0-206.0-288.0
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1224303228
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax-30.8-28.2-24.8-15.5-9.7

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.450.03180.0430.0350.04
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.670.03340.04440.03750.0425
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate109.0105.0103.3107.1106.2

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value4.10.0410.0410.0420.042
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanBenefitObligation us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanBenefitObligation

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value676654608731711724
Percentage of DefinedBenefitPlanBenefitObligation100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value119351105094621016794269079
Percentage of DefinedBenefitPlanBenefitObligation1765.51689.61556.21390.81325.71254.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value197208213241
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value3129309930473056
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter1588.31489.91430.51268.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value49525755
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value579547509518
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths1181.61051.9893.0941.8

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value44464652
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value610593580581
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive1386.41289.11260.91117.3

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value45474753
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value601586566567
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour1335.61246.81204.31069.8

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value46484853
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value598573554552
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree1300.01193.81154.21041.5

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value47494854
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value583564533531
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo1240.41151.01110.4983.3

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value502458408439420431
Percentage of DefinedBenefitPlanFairValueOfPlanAssets100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value896883956984670462135338
Percentage of DefinedBenefitPlanFairValueOfPlanAssets1786.51833.01711.81527.11479.31238.5

us-gaap:DefinedBenefitPlanFundedStatusOfPlan us-gaap:RetirementPlanTaxStatus, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:NonqualifiedPlan, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-467000000.0-452000000.0-385000000.0-420000000.0-392000000.0
Percentage of DefinedBenefitPlanFundedStatusOfPlan100.0100.0100.0100.0100.0

us-gaap:QualifiedPlan, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-2500000000.0-2203000000.0-2093000000.0-3043000000.0-2821000000.0
Percentage of DefinedBenefitPlanFundedStatusOfPlan535.3487.4543.6724.5719.6

us-gaap:DefinedBenefitPlanFundedStatusOfPlan us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-174000000.0-196000000.0-200000000.0-292000000.0-291000000.0
Percentage of DefinedBenefitPlanFundedStatusOfPlan37.343.451.969.574.2

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value-2967000000.0-2655000000.0-2478000000.0-3463000000.0-3213000000.0
Percentage of DefinedBenefitPlanFundedStatusOfPlan635.3587.4643.6824.5819.6

us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear fe:MedicareStatus, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear

fe:PostMedicare, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value5.55.50.0550.0550.055
Percentage of DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear100.0100.0100.0100.0100.0

fe:PreMedicare, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value6.06.00.060.060.06
Percentage of DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear109.1109.1109.1109.1109.1

us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage us-gaap:DefinedBenefitPlanByPlanAssetCategories

us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage

fe:AlternativeInvestments


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value8.00.080.080.08
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanCashAndCashEquivalents


Defined
Period End2020-12-312019-12-312018-12-31
Value6.00.060.06
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage75.075.075.0

us-gaap:DefinedBenefitPlanEquitySecurities


Defined
Period End2020-12-312019-12-312018-12-31
Value38.00.380.38
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage475.0475.0475.0

us-gaap:DefinedBenefitPlanRealEstate


Defined
Period End2020-12-312019-12-312018-12-31
Value10.00.10.1
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage125.0125.0125.0

us-gaap:FixedIncomeFunds


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value30.00.30.30.3
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage375.0375.0375.0375.0

us-gaap:HedgeFunds


Defined
Period End2020-12-312019-12-312018-12-31
Value8.00.080.08
Percentage of DefinedBenefitPlanPlanAssetsTargetAllocationPercentage100.0100.0100.0

us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations

fe:InsurancelinkedSecurities, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-31
Value4.00.020.02
Percentage of DefinedBenefitPlanWeightedAverageAssetAllocations100.0100.0100.0

fe:InvestmentsExcludinginInvestmentsatNAV, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value75.00.780.960.991.0
Percentage of DefinedBenefitPlanWeightedAverageAssetAllocations1875.03900.04800.00.00.0

us-gaap:CorporateDebtSecurities, us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-31
Value7.00.070.08
Percentage of DefinedBenefitPlanWeightedAverageAssetAllocations175.0350.0400.0

us-gaap:CorporateDebtSecurities, us-gaap:PensionPlansDefinedBenefit