2.4.0.8000121 - Statement - Consolidated Statements of Comprehensive Income (Loss) (Parenthetical)truefalsefalse1false USDfalsefalse$FROM_Apr01_2013_TO_Jun30_2013http://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$FROM_Apr01_2012_TO_Jun30_2012http://www.sec.gov/CIK0000004904duration2012-04-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$FROM_Jan01_2013_TO_Jun30_2013http://www.sec.gov/CIK0000004904duration2013-01-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$FROM_Jan01_2012_TO_Jun30_2012http://www.sec.gov/CIK0000004904duration2012-01-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse50000005000000USD$falsetruefalse2truefalsefalse50000005000000USD$falsetruefalse3truefalsefalse80000008000000USD$falsetruefalse4truefalsefalse1100000011000000USD$falsetruefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax2false 4us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalse3truefalsefalse00USD$falsefalsefalse4truefalsefalse10000001000000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect of the appreciation (loss) in the value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) losses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Securities Available for Sale, Tax3false 4us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse20000002000000USD$falsefalsefalse2truefalsefalse40000004000000USD$falsefalsefalse3truefalsefalse50000005000000USD$falsefalsefalse4truefalsefalse80000008000000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 false2Amortization of Pension and OPEB Deferred Costs, Tax4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_AppalachianPowerCoMemberhttp://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseAppalachian Power Co [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiaep_AppalachianPowerCoMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Appalachian Power Co [Member]5false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse4800048000USD$falsefalsefalse2truefalsefalse305000305000USD$falsefalsefalse3truefalsefalse725000725000USD$falsefalsefalse4truefalsefalse1500015000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax6false 4us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse193000193000USD$falsefalsefalse2truefalsefalse484000484000USD$falsefalsefalse3truefalsefalse386000386000USD$falsefalsefalse4truefalsefalse969000969000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 false2Amortization of Pension and OPEB Deferred Costs, Tax7false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse9false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_IndianaMichiganPowerCoMemberhttp://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseIndiana Michigan Power Co [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiaep_IndianaMichiganPowerCoMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Indiana Michigan Power Co [Member]8false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse172000172000USD$falsefalsefalse2truefalsefalse-4002000-4002000USD$falsefalsefalse3truefalsefalse18540001854000USD$falsefalsefalse4truefalsefalse-2680000-2680000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax9false 4us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse9500095000USD$falsefalsefalse2truefalsefalse150000150000USD$falsefalsefalse3truefalsefalse189000189000USD$falsefalsefalse4truefalsefalse300000300000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 false2Amortization of Pension and OPEB Deferred Costs, Tax10false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse13false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_OhioPowerCoMemberhttp://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseOhio Power Co [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiaep_OhioPowerCoMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Ohio Power Co [Member]11false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse293000293000USD$falsefalsefalse2truefalsefalse9100091000USD$falsefalsefalse3truefalsefalse281000281000USD$falsefalsefalse4truefalsefalse846000846000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax12false 4us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse17600001760000USD$falsefalsefalse2truefalsefalse17450001745000USD$falsefalsefalse3truefalsefalse35200003520000USD$falsefalsefalse4truefalsefalse34900003490000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 false2Amortization of Pension and OPEB Deferred Costs, Tax13false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse17false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PublicServiceCoOfOklahomaMemberhttp://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00falsefalsePublic Service Co Of Oklahoma [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiaep_PublicServiceCoOfOklahomaMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Public Service Co Of Oklahoma [Member]14false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse137000137000USD$falsefalsefalse2truefalsefalse193000193000USD$falsefalsefalse3truefalsefalse227000227000USD$falsefalsefalse4truefalsefalse222000222000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax15false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse21false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_SouthwesternElectricPowerCoMemberhttp://www.sec.gov/CIK0000004904duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSouthwestern Electric Power Co [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiaep_SouthwesternElectricPowerCoMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Southwestern Electric Power Co [Member]16false 4us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTaxus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse264000264000USD$falsefalsefalse2truefalsefalse213000213000USD$falsefalsefalse3truefalsefalse585000585000USD$falsefalsefalse4truefalsefalse743000743000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 false2Cash Flow Hedges, Tax17false 4us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3400034000USD$falsetruefalse2truefalsefalse9000090000USD$falsetruefalse3truefalsefalse6800068000USD$falsetruefalse4truefalsefalse179000179000USD$falsetruefalsexbrli:monetaryItemTypemonetaryTax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580 false2Amortization of Pension and OPEB Deferred Costs, TaxfalseConsolidated Statements of Comprehensive Income (Loss) (Parenthetical) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.aep.com/role/ConsolidatedStatementsOfComprehensiveIncomeLossParenthetical417