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No authoritative reference available. false 6 Outstanding collateral payments included in other assets 2 fe_OutstandingCollateralPayments fe false credit instant Outstanding collateral payments. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false true false false 245000000 245000000 false false false xbrli:monetaryItemType monetary Outstanding collateral payments. 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No authoritative reference available. false 15 Electricity production from renewable sources (In Percentage) 2 fe_ElectricityProductionFromRenewableSources fe false na duration Electricity production from renewable sources. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false true false false 25 25 false false false 3 false true false false 10 10 false false false 4 false false false false 0 0 false false false us-types:percentItemType pure Electricity production from renewable sources. 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No authoritative reference available. false 17 Total environmental liabilities 2 fe_EnvironmentalRemediationLiabilitiesAccrued fe false credit instant Environmental Remediation Liabilities Accrued. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false true false false 105000000 105000000 false false false xbrli:monetaryItemType monetary Environmental Remediation Liabilities Accrued. 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No authoritative reference available. false 23 Additional collateral payments on parental guarantees 2 fe_AdditionalCollateralPaymentsOnParentalGuarantees fe false credit instant Additional collateral payments on parental guarantees. false false false false false false false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false true false false 609000000 609000000 false false false xbrli:monetaryItemType monetary Additional collateral payments on parental guarantees. 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No authoritative reference available. false 226 Commitments, Guarantees and Contingencies (Textuals) 2 fe_CommitmentsGuaranteesAndContingenciesTextualsAbstract fe false na duration Commitments Guarantees and Contingencies. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string Commitments Guarantees and Contingencies. false 241 Total environmental liabilities 2 fe_EnvironmentalRemediationLiabilitiesAccrued fe false credit instant Environmental Remediation Liabilities Accrued. false false false false false false false false false false false verboselabel false 1 false true false false 26000000 26000000 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:monetaryItemType monetary Environmental Remediation Liabilities Accrued. No authoritative reference available. false 257 CEI [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosurecommitmentsguaranteesandcontingenciesdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false false 12 USD true false false false CEI [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi fe_SubsidiaryTwoMember dei_LegalEntityAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 258 Commitments, Guarantees and Contingencies (Textuals) 2 fe_CommitmentsGuaranteesAndContingenciesTextualsAbstract fe false na duration Commitments Guarantees and Contingencies. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string Commitments Guarantees and Contingencies. false 273 Total environmental liabilities 2 fe_EnvironmentalRemediationLiabilitiesAccrued fe false credit instant Environmental Remediation Liabilities Accrued. false false false false false false false false false false false verboselabel false 1 false true false false 1000000 1000000 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:monetaryItemType monetary Environmental Remediation Liabilities Accrued. No authoritative reference available. false 289 TE [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosurecommitmentsguaranteesandcontingenciesdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false false 13 USD true false false false TE [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi fe_SubsidiaryThreeMember dei_LegalEntityAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 290 Commitments, Guarantees and Contingencies (Textuals) 2 fe_CommitmentsGuaranteesAndContingenciesTextualsAbstract fe false na duration Commitments Guarantees and Contingencies. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string Commitments Guarantees and Contingencies. false 305 Total environmental liabilities 2 fe_EnvironmentalRemediationLiabilitiesAccrued fe false credit instant Environmental Remediation Liabilities Accrued. false false false false false false false false false false false verboselabel false 1 false true false false 1000000 1000000 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:monetaryItemType monetary Environmental Remediation Liabilities Accrued. No authoritative reference available. false 321 JCP&L [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosurecommitmentsguaranteesandcontingenciesdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false false 14 USD true false false false JCP&L [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi fe_SubsidiaryFourMember dei_LegalEntityAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. 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