1.0.0.3 true CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (USD $) In Millions, except Share data false 1 $ true false false false Common Stock [Member] us-gaap_StatementEquityComponentsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_CommonStockMember us-gaap_StatementEquityComponentsAxis explicitMember u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 false 2 $ true false false false Additional Paid In Capital [Member] us-gaap_StatementEquityComponentsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_AdditionalPaidInCapitalMember us-gaap_StatementEquityComponentsAxis explicitMember u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 3 $ true false false false Accumulated Other Comprehensive Income [Member] us-gaap_StatementEquityComponentsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_AccumulatedOtherComprehensiveIncomeMember us-gaap_StatementEquityComponentsAxis explicitMember u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 4 $ true false false false Retained Earnings [Member] us-gaap_StatementEquityComponentsAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_RetainedEarningsMember us-gaap_StatementEquityComponentsAxis explicitMember u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 5 $ true false false false Unallocated ESOP Common Stock [Member] us-gaap_StatementEquityComponentsAxis xbrldi http://xbrl.org/2006/xbrldi fe_UnallocatedEsopCommonStockMember us-gaap_StatementEquityComponentsAxis explicitMember u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 false 6 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 6 Beginning Balance (in shares) at Dec. 31, 2006 3 us-gaap_CommonStockSharesOutstanding us-gaap true na instant shares No definition available. false false false true false false true false false 1 false true 319205517 319205517.00 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 5 Beginning Balance at Dec. 31, 2006 3 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false true false false true false false 1 true true 32000000 32 true false 2 true true 6466000000 6466 true false 3 true true -259000000 -259 true false 4 true true 2806000000 2806 true false 5 true true -10000000 -10 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 7 Earnings available to FirstEnergy Corp. 3 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true 1309000000 1309 true false 5 false false 0 0 true false 6 false true 1309000000 1309 false false No definition available. No authoritative reference available. false 8 Unrealized gain on derivative hedges 3 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -17000000 -17 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 9 Unrealized gain on investments 3 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true 47000000 47 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 10 Pension and other postretirement benefits 3 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true 179000000 179 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 12 Stock options exercised 3 us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true -40000000 -40 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 13 Allocation of ESOP shares 3 fe_AllocationOfEsopShares fe false na duration monetary Undistributed shares held by the ESOP Trust that are completely distributed in 2007. false false false false false false false false false 1 false false 0 0 true false 2 false true 26000000 26 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false true 10000000 10 true false 6 false false 0 0 false false Undistributed shares held by the ESOP Trust that are completely distributed in 2007. No authoritative reference available. false 14 Restricted stock units 3 us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true 23000000 23 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 15 Stock-based compensation 3 us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true 2000000 2 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 16 FIN 48 cumulative effect adjustment 3 us-gaap_CumulativeEffectOfInitialAdoptionOfFIN48 us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true -3000000 -3 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 17 Repurchase of common stock 3 us-gaap_StockRepurchasedDuringPeriodValue us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -1000000 -1 true false 2 false true -968000000 -968 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 18 Repurchase of common stock (in shares) 4 us-gaap_StockRepurchasedDuringPeriodShares us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true -14370110 -14370110.00 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 19 Cash dividends declared on common stock 3 us-gaap_DividendsCommonStockCash us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true -625000000 -625 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 21 Ending Balance at Dec. 31, 2007 3 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false true false false false true false 1 false true 31000000 31 true false 2 false true 5509000000 5509 true false 3 false true -50000000 -50 true false 4 false true 3487000000 3487 true false 5 false true 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 22 Ending Balance (in shares) at Dec. 31, 2007 3 us-gaap_CommonStockSharesOutstanding us-gaap true na instant shares No definition available. false false false true false false false true false 1 false true 304835407 304835407.00 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 7 Earnings available to FirstEnergy Corp. 3 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true 1342000000 1342 true false 5 false false 0 0 true false 6 false true 1342000000 1342 false false No definition available. No authoritative reference available. false 8 Unrealized gain on derivative hedges 3 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -28000000 -28 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 9 Unrealized gain on investments 3 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -146000000 -146 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 10 Pension and other postretirement benefits 3 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -1156000000 -1156 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 12 Stock options exercised 3 us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true -36000000 -36 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 14 Restricted stock units 3 us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true -1000000 -1 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 15 Stock-based compensation 3 us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true 1000000 1 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 19 Cash dividends declared on common stock 3 us-gaap_DividendsCommonStockCash us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true -670000000 -670 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 21 Ending Balance at Dec. 31, 2008 3 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false true false false false true false 1 false true 31000000 31 true false 2 false true 5473000000 5473 true false 3 false true -1380000000 -1380 true false 4 false true 4159000000 4159 true false 5 false true 0 0 true false 6 false true 8315000000 8315 false false No definition available. No authoritative reference available. false 22 Ending Balance (in shares) at Dec. 31, 2008 3 us-gaap_CommonStockSharesOutstanding us-gaap true na instant shares No definition available. false false false true false false false true false 1 false true 304835407 304835407.00 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false true 304835407 304835407.00 false false No definition available. No authoritative reference available. false 7 Earnings available to FirstEnergy Corp. 3 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true 1006000000 1006 true false 5 false false 0 0 true false 6 false true 1006000000 1006 false false No definition available. No authoritative reference available. false 8 Unrealized gain on derivative hedges 3 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true 27000000 27 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 9 Unrealized gain on investments 3 us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -43000000 -43 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 10 Pension and other postretirement benefits 3 us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false true -19000000 -19 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 12 Stock options exercised 3 us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true -3000000 -3 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 14 Restricted stock units 3 us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true 7000000 7 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 15 Stock-based compensation 3 us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true 1000000 1 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 19 Cash dividends declared on common stock 3 us-gaap_DividendsCommonStockCash us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false true -670000000 -670 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 20 Acquisition adjustment of non-contrilling interest 3 us-gaap_MinorityInterestDecreaseFromRedemptions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 true false 2 false true -30000000 -30 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false false 0 0 false false No definition available. No authoritative reference available. false 21 Ending Balance at Dec. 31, 2009 3 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false true false false false true false 1 true true 31000000 31 true false 2 true true 5448000000 5448 true false 3 true true -1415000000 -1415 true false 4 true true 4495000000 4495 true false 5 true true 0 0 true false 6 true true 8557000000 8557 false false No definition available. No authoritative reference available. false 22 Ending Balance (in shares) at Dec. 31, 2009 3 us-gaap_CommonStockSharesOutstanding us-gaap true na instant shares No definition available. false false false true false false false true false 1 false true 304835407 304835407.00 true false 2 false false 0 0 true false 3 false false 0 0 true false 4 false false 0 0 true false 5 false false 0 0 true false 6 false true 304835407 304835407.00 false false No definition available. No authoritative reference available. false false 6 37 false Millions NoRounding UnKnown false true