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Basis.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-466000000-466falsefalsefalsefalsefalse2truefalsefalse-643000000-643falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair Value Liabilities Measured On Recurring Basis.No authoritative reference available.falsefalseTotal845false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://firstenergycorp.com/role/fairvalueoffinancialinstrumentsdetails51falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse383falsefalseUSDtruefalse{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Other Securities [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Other_Securities_Memberhttp://www.sec.gov/CIK0001031296instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOther Securities [Member]us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldife_OtherSecuritiesMemberus-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$384falsefalseUSDtruefalse{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Other Securities [Member] 12/31/2009 USD ($) $BalanceAsOf_31Dec2009_Other_Securities_Memberhttp://www.sec.gov/CIK0001031296instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseOther Securities [Member]us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldife_OtherSecuritiesMemberus-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOther Securities [Member]846true0fe_FairValueAssetsMeasuredOnRecurringBasisAbstractfefalsenadurationFair value assets measured on recurring basis.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringFair value assets measured on recurring basis.falsefalseAssets847false0fe_FairValueAssetsMeasuredOnRecurringBasisfefalsedebitinstantFair Value Assets Measured On Recurring Basis.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse219000000219falsetruefalsefalsefalse2truefalsefalse7500000075falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair Value Assets Measured On Recurring Basis.No authoritative reference available.falsefalseTotal2695Fair Value of Financial Instruments (Details 5) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue