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Must be disclosed if the amounts (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a false 4 Internal revenues 2 us-gaap_SegmentReportingInformationIntersegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 0 0 false false false 2 false true false false 0 0 false false false 3 false true false false 67000000 67000000 false false false 4 false true false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from transactions with other operating segments of the same entity. 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Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph e false 7 Investment income 2 us-gaap_InvestmentIncomeInterestAndDividend us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 31000000 31000000 false false false 2 false true false false 27000000 27000000 false false false 3 false true false false 47000000 47000000 false false false 4 false true false false 16000000 16000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 11 Total assets 2 us-gaap_Assets us-gaap true debit instant No definition available. 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 34306000000 34306000000 false false false 3 false false false false 0 0 false false false 4 false true false false 34306000000 34306000000 false false false 5 false true false false 34466000000 34466000000 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 43 false 13 Property additions 2 us-gaap_SegmentReportingInformationExpendituresForAdditionsToLongLivedAssets us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 489000000 489000000 false false false 2 false true false false 489000000 489000000 false false false 3 false true false false 997000000 997000000 false false false 4 false true false false 1143000000 1143000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment. Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b false 14 Segment Information (Textuals) 2 fe_SegmentInformationTextualsAbstract fe false na duration Segment Information. 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 5 false false false false 0 0 false false false xbrli:stringItemType string Segment Information. false 15 Number of customers served by utility operating companies 2 fe_NumberOfCustomersServedByUtilityOperatingCompanies fe false na duration Number of customers served by utility operating companies. 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 true false false 4500000 4500000 false false false 4 false false false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:integerItemType integer Number of customers served by utility operating companies. No authoritative reference available. false 16 Number of square miles in service territories in Ohio Pennsylvania and New Jersey 2 fe_NumberOfSquareMilesInServiceTerritoriesInOhioPennsylvaniaAndNewJersey fe false na instant Number of square miles in service territories in Ohio Pennsylvania and New Jersey. 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 false false false 0 0 false false false 5 false true false false 36100 36100 false false false xbrli:integerItemType integer Number of square miles in service territories in Ohio Pennsylvania and New Jersey. No authoritative reference available. false 17 Number of generating facilities owned or leased by competitive segment 2 fe_NumberOfGeneratingFacilitiesOwnedOrLeasedByCompetitiveSegment fe false na instant Number of generating facilities owned or leased by competitive segment. 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 false false false 0 0 false false false 5 false true false false 19 19 false false false xbrli:integerItemType integer Number of generating facilities owned or leased by competitive segment. No authoritative reference available. false 18 Megawatts of net demonstrated capacity of competitive segment 2 fe_Megawattsofnetdemonstratedcapacityofcompetitivesegment fe false na instant Megawatts of net demonstrated capacity of competitive segment. 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 false false false 0 0 false false false 5 false true false false 13710 13710 false false false xbrli:integerItemType integer Megawatts of net demonstrated capacity of competitive segment. No authoritative reference available. false 19 Energy Delivery Services [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosuresegmentinformationdetails 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 5 false false false false 0 0 false false false false 7 USD true false false false fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 8 USD true false false false fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 9 USD true false false false fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 10 USD true false false false fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentOneMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 20 Segment Financial Information 2 fe_SegmentFinancialInformationAbstract fe false na duration Segment Financial Information. 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 5 false false false false 0 0 false false false xbrli:stringItemType string Segment Financial Information. false 21 External revenues 2 us-gaap_SegmentReportingInformationRevenueFromExternalCustomers us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 2373000000 2373000000 false false false 2 false true false false 2792000000 2792000000 false false false 3 false true false false 4916000000 4916000000 false false false 4 false true false false 5813000000 5813000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from external customers for the reportable segment. Must be disclosed if the amounts (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a false 22 Internal revenues 2 us-gaap_SegmentReportingInformationIntersegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 19000000 19000000 false false false 2 false true false false 0 0 false false false 3 false true false false 19000000 19000000 false false false 4 false true false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from transactions with other operating segments of the same entity. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph b true 23 Total revenues 2 us-gaap_SegmentReportingSegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 2392000000 2392000000 false false false 2 false true false false 2792000000 2792000000 false false false 3 false true false false 4935000000 4935000000 false false false 4 false true false false 5813000000 5813000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total revenues for reportable segments. 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Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph e false 25 Investment income 2 us-gaap_InvestmentIncomeInterestAndDividend us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 27000000 27000000 false false false 2 false true false false 35000000 35000000 false false false 3 false true false false 52000000 52000000 false false false 4 false true false false 65000000 65000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies. 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Reporting interest revenue net of interest expense is permitted only when a majority of the segment's revenues are from interest and the chief operating decision maker relies primarily on net interest revenue to assess the performance of the segment and make decisions about resources to be allocated to the segment. In all other segment disclosure situations, interest revenue must be reported separately from interest expense. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b false 28 NET INCOME 2 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 143000000 143000000 false false false 2 false true false false 154000000 154000000 false false false 3 false true false false 257000000 257000000 false false false 4 false true false false 136000000 136000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 29 Total assets 2 us-gaap_Assets us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 22450000000 22450000000 false false false 2 false true false false 23215000000 23215000000 false false false 3 false true false false 22450000000 22450000000 false false false 4 false true false false 23215000000 23215000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. 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Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b false 37 Competitive Energy Services [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosuresegmentinformationdetails 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 5 false false false false 0 0 false false false false 11 USD true false false false fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 12 USD true false false false fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 13 USD true false false false fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 14 USD true false false false fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_SegmentTwoMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 38 Segment Financial Information 2 fe_SegmentFinancialInformationAbstract fe false na duration Segment Financial Information. 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 5 false false false false 0 0 false false false xbrli:stringItemType string Segment Financial Information. false 39 External revenues 2 us-gaap_SegmentReportingInformationRevenueFromExternalCustomers us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 778000000 778000000 false false false 2 false true false false 504000000 504000000 false false false 3 false true false false 1494000000 1494000000 false false false 4 false true false false 839000000 839000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from external customers for the reportable segment. Must be disclosed if the amounts (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a false 40 Internal revenues 2 us-gaap_SegmentReportingInformationIntersegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 539000000 539000000 false false false 2 false true false false 839000000 839000000 false false false 3 false true false false 1213000000 1213000000 false false false 4 false true false false 1732000000 1732000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from transactions with other operating segments of the same entity. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph b true 41 Total revenues 2 us-gaap_SegmentReportingSegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 1317000000 1317000000 false false false 2 false true false false 1343000000 1343000000 false false false 3 false true false false 2707000000 2707000000 false false false 4 false true false false 2571000000 2571000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total revenues for reportable segments. 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Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph e false 43 Investment income 2 us-gaap_InvestmentIncomeInterestAndDividend us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 13000000 13000000 false false false 2 false true false false 6000000 6000000 false false false 3 false true false false 14000000 14000000 false false false 4 false true false false -23000000 -23000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies. 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Reporting interest revenue net of interest expense is permitted only when a majority of the segment's revenues are from interest and the chief operating decision maker relies primarily on net interest revenue to assess the performance of the segment and make decisions about resources to be allocated to the segment. In all other segment disclosure situations, interest revenue must be reported separately from interest expense. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b false 46 NET INCOME 2 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 125000000 125000000 false false false 2 false true false false 276000000 276000000 false false false 3 false true false false 201000000 201000000 false false false 4 false true false false 431000000 431000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 47 Total assets 2 us-gaap_Assets us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 11100000000 11100000000 false false false 2 false true false false 10144000000 10144000000 false false false 3 false true false false 11100000000 11100000000 false false false 4 false true false false 10144000000 10144000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 43 false 49 Property additions 2 us-gaap_SegmentReportingInformationExpendituresForAdditionsToLongLivedAssets us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 282000000 282000000 false false false 2 false true false false 248000000 248000000 false false false 3 false true false false 605000000 605000000 false false false 4 false true false false 669000000 669000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment. Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b false 55 Other Business Operations [Member] 0 na true na na No definition available. false true false false false false false false false false false http://firstenergycorp.com/role/disclosuresegmentinformationdetails 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 5 false false false false 0 0 false false false false 15 USD true false false false fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 16 USD true false false false fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 17 USD true false false false fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 18 USD true false false false fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi fe_OtherBusinessOperationsMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 56 Segment Financial Information 2 fe_SegmentFinancialInformationAbstract fe false na duration Segment Financial Information. 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 5 false false false false 0 0 false false false xbrli:stringItemType string Segment Financial Information. false 57 External revenues 2 us-gaap_SegmentReportingInformationRevenueFromExternalCustomers us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 6000000 6000000 false false false 2 false true false false 5000000 5000000 false false false 3 false true false false 10000000 10000000 false false false 4 false true false false 12000000 12000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from external customers for the reportable segment. Must be disclosed if the amounts (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a false 58 Internal revenues 2 us-gaap_SegmentReportingInformationIntersegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 0 0 false false false 2 false true false false 0 0 false false false 3 false true false false 0 0 false false false 4 false true false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of revenue from transactions with other operating segments of the same entity. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph b true 59 Total revenues 2 us-gaap_SegmentReportingSegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 6000000 6000000 false false false 2 false true false false 5000000 5000000 false false false 3 false true false false 10000000 10000000 false false false 4 false true false false 12000000 12000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total revenues for reportable segments. 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Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph e false 61 Investment income 2 us-gaap_InvestmentIncomeInterestAndDividend us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 0 0 false false false 2 false true false false 0 0 false false false 3 false true false false 0 0 false false false 4 false true false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies. 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Reporting interest revenue net of interest expense is permitted only when a majority of the segment's revenues are from interest and the chief operating decision maker relies primarily on net interest revenue to assess the performance of the segment and make decisions about resources to be allocated to the segment. In all other segment disclosure situations, interest revenue must be reported separately from interest expense. 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Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. 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Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. 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Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph b true 77 Total revenues 2 us-gaap_SegmentReportingSegmentRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false -587000000 -587000000 false false false 2 false true false false -869000000 -869000000 false false false 3 false true false false -1225000000 -1225000000 false false false 4 false true false false -1791000000 -1791000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total revenues for reportable segments. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 32 -Subparagraph a false 78 Depreciation and amortization 2 us-gaap_SegmentReportingInformationDepreciationDepletionAndAmortizationExpense us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 3000000 3000000 false false false 2 false true false false 4000000 4000000 false false false 3 false true false false 4000000 4000000 false false false 4 false true false false 7000000 7000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of depreciation, depletion, and amortization expense for the reportable segment. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph e false 79 Investment income 2 us-gaap_InvestmentIncomeInterestAndDividend us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false -9000000 -9000000 false false false 2 false true false false -14000000 -14000000 false false false 3 false true false false -19000000 -19000000 false false false 4 false true false false -26000000 -26000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Income derived from investments in debt and equity securities and on cash and cash equivalents. Interest income represents earnings which reflect the time value of money or transactions in which the payments are for the use or forbearance of money. Dividend income represents a distribution of earnings to shareholders by investee companies. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 14 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a, b -Article 5 false 80 Net interest charges 2 us-gaap_SegmentReportingInformationInterestIncomeExpenseNet us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 10000000 10000000 false false false 2 false true false false 40000000 40000000 false false false 3 false true false false 27000000 27000000 false false false 4 false true false false 78000000 78000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Amount of interest revenue net of interest expense for the reportable segment. Reporting interest revenue net of interest expense is permitted only when a majority of the segment's revenues are from interest and the chief operating decision maker relies primarily on net interest revenue to assess the performance of the segment and make decisions about resources to be allocated to the segment. In all other segment disclosure situations, interest revenue must be reported separately from interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph end false 81 Income taxes 2 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false -9000000 -9000000 false false false 2 false true false false -20000000 -20000000 false false false 3 false true false false -18000000 -18000000 false false false 4 false true false false -40000000 -40000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b false 82 NET INCOME 2 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false -28000000 -28000000 false false false 2 false true false false -40000000 -40000000 false false false 3 false true false false -54000000 -54000000 false false false 4 false true false false -79000000 -79000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 83 Total assets 2 us-gaap_Assets us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 325000000 325000000 false false false 2 false true false false 263000000 263000000 false false false 3 false true false false 325000000 325000000 false false false 4 false true false false 263000000 263000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 false 84 Goodwill 2 us-gaap_Goodwill us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 0 0 false false false 2 false true false false 0 0 false false false 3 false true false false 0 0 false false false 4 false true false false 0 0 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 43 false 85 Property additions 2 us-gaap_SegmentReportingInformationExpendituresForAdditionsToLongLivedAssets us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 28000000 28000000 false false false 2 true true false false -7000000 -7000000 false false false 3 true true false false 44000000 44000000 false false false 4 true true false false 12000000 12000000 false false false 5 false false false false 0 0 false false false xbrli:monetaryItemType monetary Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment. Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b false 5 69 false NoRounding UnKnown UnKnown false true