0000004904false2020Q2--12-3100017217810001702494000000687900000501720000073986000008102700000924875500000049042020-01-012020-06-300000004904aep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904aep:OhioPowerCoMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMember2020-01-012020-06-300000004904exch:XNYSus-gaap:CommonStockMember2020-01-012020-06-300000004904exch:XNYSus-gaap:PreferredStockMember2020-01-012020-06-30xbrli:shares00000049042020-08-060000004904aep:AEPTexasInc.Member2020-08-060000004904aep:AppalachianPowerCoMember2020-08-060000004904aep:IndianaMichiganPowerCoMember2020-08-060000004904aep:OhioPowerCoMember2020-08-060000004904aep:PublicServiceCoOfOklahomaMember2020-08-060000004904aep:SouthwesternElectricPowerCoMember2020-08-06iso4217:USD0000004904us-gaap:ElectricityMember2020-04-012020-06-300000004904us-gaap:ElectricityMember2019-04-012019-06-300000004904us-gaap:ElectricityMember2020-01-012020-06-300000004904us-gaap:ElectricityMember2019-01-012019-06-300000004904aep:TransmissionandDistributionUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:TransmissionandDistributionUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:TransmissionandDistributionUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:TransmissionandDistributionUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:OtherRevenuesMember2020-04-012020-06-300000004904aep:OtherRevenuesMember2019-04-012019-06-300000004904aep:OtherRevenuesMember2020-01-012020-06-300000004904aep:OtherRevenuesMember2019-01-012019-06-3000000049042020-04-012020-06-3000000049042019-04-012019-06-3000000049042019-01-012019-06-300000004904us-gaap:ElectricityGenerationMember2020-04-012020-06-300000004904us-gaap:ElectricityGenerationMember2019-04-012019-06-300000004904us-gaap:ElectricityGenerationMember2020-01-012020-06-300000004904us-gaap:ElectricityGenerationMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMember2019-01-012019-06-30iso4217:USDxbrli:shares0000004904us-gaap:CommonStockMember2018-12-310000004904us-gaap:AdditionalPaidInCapitalMember2018-12-310000004904us-gaap:RetainedEarningsMember2018-12-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904us-gaap:NoncontrollingInterestMember2018-12-3100000049042018-12-310000004904us-gaap:CommonStockMember2019-01-012019-03-310000004904us-gaap:AdditionalPaidInCapitalMember2019-01-012019-03-3100000049042019-01-012019-03-310000004904us-gaap:RetainedEarningsMember2019-01-012019-03-310000004904us-gaap:NoncontrollingInterestMember2019-01-012019-03-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904us-gaap:CommonStockMember2019-03-310000004904us-gaap:AdditionalPaidInCapitalMember2019-03-310000004904us-gaap:RetainedEarningsMember2019-03-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904us-gaap:NoncontrollingInterestMember2019-03-3100000049042019-03-310000004904us-gaap:CommonStockMember2019-04-012019-06-300000004904us-gaap:AdditionalPaidInCapitalMember2019-04-012019-06-300000004904us-gaap:RetainedEarningsMember2019-04-012019-06-300000004904us-gaap:NoncontrollingInterestMember2019-04-012019-06-300000004904us-gaap:NoncontrollingInterestMemberaep:AEPWindHoldingsLLCMember2019-04-012019-06-300000004904aep:AEPWindHoldingsLLCMember2019-04-012019-06-300000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904us-gaap:CommonStockMember2019-06-300000004904us-gaap:AdditionalPaidInCapitalMember2019-06-300000004904us-gaap:RetainedEarningsMember2019-06-300000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904us-gaap:NoncontrollingInterestMember2019-06-3000000049042019-06-300000004904us-gaap:CommonStockMember2019-12-310000004904us-gaap:AdditionalPaidInCapitalMember2019-12-310000004904us-gaap:RetainedEarningsMember2019-12-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904us-gaap:NoncontrollingInterestMember2019-12-3100000049042019-12-310000004904us-gaap:CommonStockMember2020-01-012020-03-310000004904us-gaap:AdditionalPaidInCapitalMember2020-01-012020-03-3100000049042020-01-012020-03-310000004904us-gaap:RetainedEarningsMember2020-01-012020-03-310000004904us-gaap:NoncontrollingInterestMember2020-01-012020-03-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310000004904us-gaap:CommonStockMember2020-03-310000004904us-gaap:AdditionalPaidInCapitalMember2020-03-310000004904us-gaap:RetainedEarningsMember2020-03-310000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904us-gaap:NoncontrollingInterestMember2020-03-3100000049042020-03-310000004904us-gaap:CommonStockMember2020-04-012020-06-300000004904us-gaap:AdditionalPaidInCapitalMember2020-04-012020-06-300000004904us-gaap:RetainedEarningsMember2020-04-012020-06-300000004904us-gaap:NoncontrollingInterestMember2020-04-012020-06-300000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:CommonStockMember2020-06-300000004904us-gaap:AdditionalPaidInCapitalMember2020-06-300000004904us-gaap:RetainedEarningsMember2020-06-300000004904us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904us-gaap:NoncontrollingInterestMember2020-06-3000000049042020-06-300000004904srt:SubsidiariesMember2020-06-300000004904srt:SubsidiariesMember2019-12-310000004904us-gaap:NoncontrollingInterestMember2020-01-012020-06-300000004904us-gaap:NoncontrollingInterestMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:OtherRevenuesMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:OtherRevenuesMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:OtherRevenuesMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:OtherRevenuesMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904us-gaap:ElectricityGenerationMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904us-gaap:ElectricityGenerationMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904us-gaap:ElectricityGenerationMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904us-gaap:ElectricityGenerationMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2018-12-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904aep:AEPTexasInc.Member2018-12-310000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2019-01-012019-03-310000004904aep:AEPTexasInc.Member2019-01-012019-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2019-01-012019-03-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2019-03-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904aep:AEPTexasInc.Member2019-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2019-06-300000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904aep:AEPTexasInc.Member2019-06-300000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2019-12-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904aep:AEPTexasInc.Member2019-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2020-01-012020-03-310000004904aep:AEPTexasInc.Member2020-01-012020-03-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2020-03-310000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904aep:AEPTexasInc.Member2020-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904us-gaap:RetainedEarningsMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AEPTexasInc.Memberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904aep:AEPTexasInc.Member2020-06-300000004904aep:AEPTexasTransitionFundingandRestorationFundingMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AEPTexasTransitionFundingandRestorationFundingMemberaep:AEPTexasInc.Member2019-12-310000004904us-gaap:ElectricTransmissionMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904us-gaap:ElectricTransmissionMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:AEPTransmissionCoMember2020-04-012020-06-300000004904aep:AEPTransmissionCoMember2019-04-012019-06-300000004904aep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:OtherRevenuesMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904aep:OtherRevenuesMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904aep:OtherRevenuesMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:OtherRevenuesMemberaep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2018-12-310000004904aep:AEPTransmissionCoMember2018-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2019-01-012019-03-310000004904aep:AEPTransmissionCoMember2019-01-012019-03-310000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2019-03-310000004904aep:AEPTransmissionCoMember2019-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2019-06-300000004904aep:AEPTransmissionCoMember2019-06-300000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2019-12-310000004904aep:AEPTransmissionCoMember2019-12-310000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2020-01-012020-03-310000004904aep:AEPTransmissionCoMember2020-01-012020-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2020-01-012020-03-310000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2020-03-310000004904aep:AEPTransmissionCoMember2020-03-310000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904aep:AEPTransmissionCoMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904us-gaap:RetainedEarningsMemberaep:AEPTransmissionCoMember2020-06-300000004904aep:AEPTransmissionCoMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:OtherRevenuesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:OtherRevenuesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:OtherRevenuesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:OtherRevenuesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityGenerationMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityGenerationMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityGenerationMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityGenerationMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityPurchasedMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityPurchasedMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityPurchasedMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ElectricityPurchasedMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2018-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2018-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904aep:AppalachianPowerCoMember2018-12-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2019-01-012019-03-310000004904aep:AppalachianPowerCoMember2019-01-012019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904aep:AppalachianPowerCoMember2019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904aep:AppalachianPowerCoMember2019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904aep:AppalachianPowerCoMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2020-01-012020-03-310000004904aep:AppalachianPowerCoMember2020-01-012020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904aep:AppalachianPowerCoMember2020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:CommonStockMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:RetainedEarningsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904aep:AppalachianPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ElectricityMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ElectricityMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ElectricityMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ElectricityMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherRevenuesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherRevenuesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherRevenuesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherRevenuesMember2019-01-012019-06-300000004904us-gaap:ElectricityGenerationMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904us-gaap:ElectricityGenerationMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904us-gaap:ElectricityGenerationMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904us-gaap:ElectricityGenerationMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2018-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2018-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904aep:IndianaMichiganPowerCoMember2018-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2019-01-012019-03-310000004904aep:IndianaMichiganPowerCoMember2019-01-012019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904aep:IndianaMichiganPowerCoMember2019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904aep:IndianaMichiganPowerCoMember2019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904aep:IndianaMichiganPowerCoMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2020-01-012020-03-310000004904aep:IndianaMichiganPowerCoMember2020-01-012020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904aep:IndianaMichiganPowerCoMember2020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CommonStockMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:RetainedEarningsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904aep:IndianaMichiganPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:DccFuelMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:DccFuelMember2019-12-310000004904aep:OhioPowerCoMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:OhioPowerCoMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:OhioPowerCoMember2020-04-012020-06-300000004904aep:OhioPowerCoMember2019-04-012019-06-300000004904aep:OhioPowerCoMember2019-01-012019-06-300000004904aep:OtherRevenuesMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:OtherRevenuesMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:OtherRevenuesMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:OtherRevenuesMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2018-12-310000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2018-12-310000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904aep:OhioPowerCoMember2018-12-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2019-01-012019-03-310000004904aep:OhioPowerCoMember2019-01-012019-03-310000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2019-03-310000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2019-03-310000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904aep:OhioPowerCoMember2019-03-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2019-06-300000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2019-06-300000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904aep:OhioPowerCoMember2019-06-300000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2019-12-310000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2019-12-310000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904aep:OhioPowerCoMember2019-12-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2020-01-012020-03-310000004904aep:OhioPowerCoMember2020-01-012020-03-310000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2020-03-310000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2020-03-310000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904aep:OhioPowerCoMember2020-03-310000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberus-gaap:CommonStockMember2020-06-300000004904aep:OhioPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904us-gaap:RetainedEarningsMemberaep:OhioPowerCoMember2020-06-300000004904aep:OhioPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904aep:OhioPowerCoMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherRevenuesMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherRevenuesMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherRevenuesMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherRevenuesMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityGenerationMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityGenerationMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityGenerationMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityGenerationMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityPurchasedMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityPurchasedMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityPurchasedMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:ElectricityPurchasedMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2018-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2018-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904aep:PublicServiceCoOfOklahomaMember2018-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2019-01-012019-03-310000004904aep:PublicServiceCoOfOklahomaMember2019-01-012019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904aep:PublicServiceCoOfOklahomaMember2019-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904aep:PublicServiceCoOfOklahomaMember2019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2020-01-012020-03-310000004904aep:PublicServiceCoOfOklahomaMember2020-01-012020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904aep:PublicServiceCoOfOklahomaMember2020-03-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:CommonStockMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:RetainedEarningsMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherRevenuesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherRevenuesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherRevenuesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherRevenuesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityGenerationMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityGenerationMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityGenerationMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityGenerationMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityPurchasedMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityPurchasedMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityPurchasedMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ElectricityPurchasedMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2018-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2018-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2018-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2018-12-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2018-12-310000004904aep:SouthwesternElectricPowerCoMember2018-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2019-01-012019-03-310000004904aep:SouthwesternElectricPowerCoMember2019-01-012019-03-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2019-01-012019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-01-012019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-03-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2019-03-310000004904aep:SouthwesternElectricPowerCoMember2019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2019-04-012019-06-300000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-06-300000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2019-06-300000004904aep:SouthwesternElectricPowerCoMember2019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2019-12-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:SouthwesternElectricPowerCoMember2019-12-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2020-01-012020-03-310000004904aep:SouthwesternElectricPowerCoMember2020-01-012020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2020-01-012020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-03-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2020-03-310000004904aep:SouthwesternElectricPowerCoMember2020-03-310000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:CommonStockMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AdditionalPaidInCapitalMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:RetainedEarningsMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedOtherComprehensiveIncomeMember2020-06-300000004904us-gaap:NoncontrollingInterestMemberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:SabineMiningCoMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:SabineMiningCoMember2019-12-31xbrli:pure0000004904us-gaap:SubsequentEventMember2020-08-012020-08-060000004904aep:LumpSumSalaryPaymentsAndCashSubsidiesMemberus-gaap:SubsequentEventMember2020-08-012020-08-060000004904aep:IncrementalLongTermIncentivePlanGrantsMemberus-gaap:SubsequentEventMember2020-08-012020-08-060000004904aep:RestrictedStockUnitsandPerformanceShareUnitsMember2020-04-012020-06-300000004904aep:RestrictedStockUnitsandPerformanceShareUnitsMember2019-04-012019-06-300000004904aep:RestrictedStockUnitsandPerformanceShareUnitsMember2020-01-012020-06-300000004904aep:RestrictedStockUnitsandPerformanceShareUnitsMember2019-01-012019-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-03-310000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-03-310000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-04-012020-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-04-012020-06-300000004904aep:InterestRateMemberus-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-04-012020-06-300000004904aep:InterestRateMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-03-310000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-03-310000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-04-012019-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-04-012019-06-300000004904aep:InterestRateMemberus-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-04-012019-06-300000004904aep:InterestRateMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-12-310000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-12-310000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-01-012020-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-01-012020-06-300000004904aep:InterestRateMemberus-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2020-01-012020-06-300000004904aep:InterestRateMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2018-12-310000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2018-12-310000004904us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-01-012019-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-01-012019-06-300000004904aep:InterestRateMemberus-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904us-gaap:ElectricityPurchasedMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberus-gaap:CommodityContractMember2019-01-012019-06-300000004904aep:InterestRateMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2020-03-310000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2019-03-310000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2019-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2019-12-310000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2018-12-310000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberaep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-03-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-03-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-12-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2018-12-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-03-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-03-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-12-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2018-12-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-03-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-03-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-03-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-04-012019-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-12-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2018-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2018-12-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember2019-01-012019-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:AccumulatedDefinedBenefitPlansAdjustmentMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember2019-01-012019-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberaep:AppleBlossomandBlackOakMember2020-04-012020-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberaep:AppleBlossomandBlackOakMember2020-01-012020-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberaep:AppleBlossomandBlackOakMember2019-04-012019-06-300000004904aep:InterestRateMemberus-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMemberaep:AppleBlossomandBlackOakMember2019-01-012019-06-300000004904aep:OklaunionGeneratingStationUnitNo1Memberaep:PublicServiceCoOfOklahomaMemberaep:GeneratingUnitsProbableofAbandonmentMember2020-06-300000004904aep:OklaunionGeneratingStationUnitNo1Memberaep:PublicServiceCoOfOklahomaMemberaep:GeneratingUnitsProbableofAbandonmentMember2020-01-012020-06-300000004904aep:DoletHillsGeneratingStationUnitNo1Memberaep:SouthwesternElectricPowerCoMemberaep:GeneratingUnitsProbableofAbandonmentMember2020-06-300000004904aep:DoletHillsGeneratingStationUnitNo1Memberaep:SouthwesternElectricPowerCoMemberaep:GeneratingUnitsProbableofAbandonmentMember2020-01-012020-06-300000004904aep:DoletHillsGeneratingStationUnitNo1Memberaep:SouthwesternElectricPowerCoMember2020-01-012020-06-300000004904aep:DoletHillsGeneratingStationUnitNo1Memberaep:SouthwesternElectricPowerCoMemberaep:GeneratingUnitsProbableofAbandonmentMember2020-04-012020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:OklaunionPowerStationAcceleratedDepreciationMember2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:OklaunionPowerStationAcceleratedDepreciationMember2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:KentuckyDeferredPurchasePowerExpensesMember2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:KentuckyDeferredPurchasePowerExpensesMember2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:PlantRetirementCostsUnrecoveredPlantMember2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:PlantRetirementCostsUnrecoveredPlantMember2019-12-310000004904aep:DoletHillsPowerStationAcceleratedDepreciationMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2020-06-300000004904aep:DoletHillsPowerStationAcceleratedDepreciationMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:COVID19Member2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:COVID19Member2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationRelatedtoRetiredPlantsMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationRelatedtoRetiredPlantsMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberus-gaap:StormCostsMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberus-gaap:StormCostsMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:CookPlantStudyCostsMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:CookPlantStudyCostsMember2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMemberaep:A2019TexasBaseRateCaseMember2020-06-300000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMemberaep:AEPTexasInc.Member2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMemberaep:AEPTexasInc.Member2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Memberaep:COVID19Member2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Memberaep:COVID19Member2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Member2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Member2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Member2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AEPTexasInc.Member2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:VegetationManagementMemberaep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:COVID19VirginiaMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:COVID19VirginiaMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:MaterialsandSuppliesRelatedtoRetiredPlantsMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:MaterialsandSuppliesRelatedtoRetiredPlantsMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationRelatedtoRetiredPlantsMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationRelatedtoRetiredPlantsMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19WestVirginiaMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19WestVirginiaMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:AppalachianPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:CookPlantStudyCostsMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:CookPlantStudyCostsMember2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMemberus-gaap:StormCostsMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMemberus-gaap:StormCostsMember2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMember2019-12-310000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMember2020-06-300000004904aep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:OhioPowerCoMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:OklaunionPowerStationAcceleratedDepreciationMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:OklaunionPowerStationAcceleratedDepreciationMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberus-gaap:StormCostsMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberus-gaap:StormCostsMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:PlantRetirementCostsUnrecoveredPlantLouisianaMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMemberaep:PlantRetirementCostsUnrecoveredPlantLouisianaMember2019-12-310000004904aep:DoletHillsPowerStationAcceleratedDepreciationMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2020-06-300000004904aep:DoletHillsPowerStationAcceleratedDepreciationMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:RegulatoryAssetsCurrentlyEarningReturnMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationLouisianaMember2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:AssetRetirementObligationLouisianaMember2019-12-310000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2020-06-300000004904aep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMemberaep:COVID19Member2019-12-310000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:OtherRegulatoryAssetsNotYetBeingRecoveredMemberaep:RegulatoryAssetsCurrentlyNotEarningReturnMemberaep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryAssetsPendingFinalRegulatoryApprovalMember2019-12-310000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Memberaep:VegetationManagementMember2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Memberaep:CapitalInvestmentsMember2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Memberaep:RateCaseExpenseMember2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Memberaep:ExcessADITandExcessFederalIncomeTaxestoDistributionCustomersMember2020-01-012020-06-300000004904aep:ExcessADITandExcessFederalIncomeTaxestoTransmissionCustomersMemberaep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:AEPTexasInc.Memberaep:PreviouslyCollectedRatesSubjecttoReconciliationMember2020-01-012020-06-300000004904aep:A2019TexasBaseRateCaseMemberaep:Amountof2019InvestmentsMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:HurricaneHannaMemberaep:AEPTexasInc.Memberus-gaap:SubsequentEventMember2020-07-012020-08-060000004904aep:AEPTexasInc.Memberaep:AEPTexasInterimTransmissionAndDistributionRatesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberaep:PlantRetirementCostsUnrecoveredPlantMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberaep:PlantRetirementCostsUnrecoveredPlantMember2020-01-012020-06-300000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMember2020-06-300000004904aep:VirginiaJurisdictionalAMRMetersMemberaep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberaep:VirginiaJurisdictionalAMIMetersMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberaep:VirginiaJurisdictionalAMIMetersMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberus-gaap:SubsequentEventMember2020-07-012020-08-060000004904aep:CapitalExpendituresIncurredForTheAmosAndMountaineerCoalFiredGeneratingPlantsMemberaep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberus-gaap:SubsequentEventMember2020-07-012020-08-060000004904aep:AppalachianPowerCoMemberaep:VirginiaLegislationAffectingBiennialReviewsMemberaep:PrepaidPensionAndOPEBAssetsMemberus-gaap:SubsequentEventMember2020-07-012020-08-060000004904aep:WestVirginiaENECAndVegetationManagementRidersMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:WestVirginiaENECAndVegetationManagementRidersMember2020-01-012020-06-300000004904aep:ETTInterimTransmissionRatesMember2020-01-012020-06-300000004904aep:A2019IndianaBaseRateCaseMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904aep:KentuckyTaxReformMember2020-01-012020-06-300000004904aep:A2020KentuckyBaseRateCaseMember2020-01-012020-06-300000004904aep:A2020OhioBaseRateCaseMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:A2012TexasBaseRateCaseMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:A2012TexasBaseRateCaseMemberaep:TurkGeneratingPlantMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:A2012TexasBaseRateCaseMemberaep:TurkGeneratingPlantMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:A2016TexasBaseRateCaseMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:Louisiana2018FormulaRateFilingMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:Louisiana2018FormulaRateFilingMemberus-gaap:SubsequentEventMember2020-07-012020-08-060000004904aep:June2022Memberaep:LettersOfCreditMember2020-06-300000004904aep:LettersOfCreditMember2020-06-300000004904aep:AEPTexasInc.Memberaep:LettersOfCreditMember2020-06-300000004904aep:OhioPowerCoMemberaep:LettersOfCreditMember2020-06-300000004904aep:RockportLeaseMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RockportLeaseMember2020-06-300000004904aep:BoatandBargeLeasesMember2020-06-30utr:MW0000004904aep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMember2019-04-012019-06-300000004904aep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMember2019-01-012019-06-30utr:Rate0000004904aep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMember2019-06-300000004904us-gaap:EquityMethodInvestmentsMemberaep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMember2019-01-012019-06-300000004904aep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMemberus-gaap:NoncontrollingInterestMember2019-01-012019-06-300000004904aep:AEPWindHoldingsLLCMemberaep:GenerationAndMarketingMember2020-06-300000004904aep:SantaRitaEastMemberaep:GenerationAndMarketingMember2019-09-300000004904aep:SantaRitaEastMemberaep:GenerationAndMarketingMember2019-01-012019-09-300000004904aep:ConesvilleGeneratingStationUnitNo4Memberaep:GenerationAndMarketingMember2020-04-012020-06-300000004904aep:ConesvilleGeneratingStationUnitNo4Memberaep:GenerationAndMarketingMember2020-06-012020-06-300000004904aep:ConesvilleGeneratingStationUnitNo4Membersrt:ScenarioForecastMemberaep:GenerationAndMarketingMember2020-10-012021-04-300000004904aep:ConesvilleGeneratingStationUnitNo4Membersrt:ScenarioForecastMemberaep:GenerationAndMarketingMember2021-07-012022-07-310000004904us-gaap:PensionPlansDefinedBenefitMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMember2019-04-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-04-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMember2019-01-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-01-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AppalachianPowerCoMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AppalachianPowerCoMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AppalachianPowerCoMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:AppalachianPowerCoMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:PublicServiceCoOfOklahomaMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:PublicServiceCoOfOklahomaMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:PublicServiceCoOfOklahomaMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:PublicServiceCoOfOklahomaMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-01-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:SouthwesternElectricPowerCoMember2020-04-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:SouthwesternElectricPowerCoMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-04-012019-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:SouthwesternElectricPowerCoMember2020-01-012020-06-300000004904us-gaap:PensionPlansDefinedBenefitMemberaep:SouthwesternElectricPowerCoMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember2019-01-012019-06-300000004904aep:VerticallyIntegratedUtilitiesMemberus-gaap:ElectricityMember2020-04-012020-06-300000004904aep:TransmissionAndDistributionCompaniesMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-04-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:TransmissionOperationsMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberaep:GenerationAndMarketingMember2020-04-012020-06-300000004904aep:OtherRevenuesMemberus-gaap:AllOtherSegmentsMember2020-04-012020-06-300000004904srt:ConsolidationEliminationsMember2020-04-012020-06-300000004904aep:VerticallyIntegratedUtilitiesMember2020-04-012020-06-300000004904aep:TransmissionAndDistributionCompaniesMember2020-04-012020-06-300000004904aep:TransmissionOperationsMember2020-04-012020-06-300000004904aep:GenerationAndMarketingMember2020-04-012020-06-300000004904us-gaap:AllOtherSegmentsMember2020-04-012020-06-300000004904aep:VerticallyIntegratedUtilitiesMemberus-gaap:ElectricityMember2019-04-012019-06-300000004904aep:TransmissionAndDistributionCompaniesMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-04-012019-06-300000004904us-gaap:ElectricTransmissionMemberaep:TransmissionOperationsMember2019-04-012019-06-300000004904aep:GenerationAndMarketingRevenuesMemberaep:GenerationAndMarketingMember2019-04-012019-06-300000004904aep:OtherRevenuesMemberus-gaap:AllOtherSegmentsMember2019-04-012019-06-300000004904srt:ConsolidationEliminationsMember2019-04-012019-06-300000004904aep:VerticallyIntegratedUtilitiesMember2019-04-012019-06-300000004904aep:TransmissionAndDistributionCompaniesMember2019-04-012019-06-300000004904aep:TransmissionOperationsMember2019-04-012019-06-300000004904aep:GenerationAndMarketingMember2019-04-012019-06-300000004904us-gaap:AllOtherSegmentsMember2019-04-012019-06-300000004904aep:VerticallyIntegratedUtilitiesMemberus-gaap:ElectricityMember2020-01-012020-06-300000004904aep:TransmissionAndDistributionCompaniesMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2020-01-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:TransmissionOperationsMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMemberaep:GenerationAndMarketingMember2020-01-012020-06-300000004904aep:OtherRevenuesMemberus-gaap:AllOtherSegmentsMember2020-01-012020-06-300000004904srt:ConsolidationEliminationsMember2020-01-012020-06-300000004904aep:VerticallyIntegratedUtilitiesMember2020-01-012020-06-300000004904aep:TransmissionAndDistributionCompaniesMember2020-01-012020-06-300000004904aep:TransmissionOperationsMember2020-01-012020-06-300000004904aep:GenerationAndMarketingMember2020-01-012020-06-300000004904us-gaap:AllOtherSegmentsMember2020-01-012020-06-300000004904aep:VerticallyIntegratedUtilitiesMemberus-gaap:ElectricityMember2019-01-012019-06-300000004904aep:TransmissionAndDistributionCompaniesMemberaep:TransmissionandDistributionUtilitiesRevenuesMember2019-01-012019-06-300000004904us-gaap:ElectricTransmissionMemberaep:TransmissionOperationsMember2019-01-012019-06-300000004904aep:GenerationAndMarketingRevenuesMemberaep:GenerationAndMarketingMember2019-01-012019-06-300000004904aep:OtherRevenuesMemberus-gaap:AllOtherSegmentsMember2019-01-012019-06-300000004904srt:ConsolidationEliminationsMember2019-01-012019-06-300000004904aep:VerticallyIntegratedUtilitiesMember2019-01-012019-06-300000004904aep:TransmissionAndDistributionCompaniesMember2019-01-012019-06-300000004904aep:TransmissionOperationsMember2019-01-012019-06-300000004904aep:GenerationAndMarketingMember2019-01-012019-06-300000004904us-gaap:AllOtherSegmentsMember2019-01-012019-06-300000004904aep:VerticallyIntegratedUtilitiesMember2020-06-300000004904aep:TransmissionAndDistributionCompaniesMember2020-06-300000004904aep:TransmissionOperationsMember2020-06-300000004904aep:GenerationAndMarketingMember2020-06-300000004904us-gaap:AllOtherSegmentsMember2020-06-300000004904srt:ConsolidationEliminationsMember2020-06-300000004904aep:VerticallyIntegratedUtilitiesMember2019-12-310000004904aep:TransmissionAndDistributionCompaniesMember2019-12-310000004904aep:TransmissionOperationsMember2019-12-310000004904aep:GenerationAndMarketingMember2019-12-310000004904us-gaap:AllOtherSegmentsMember2019-12-310000004904srt:ConsolidationEliminationsMember2019-12-310000004904us-gaap:ElectricTransmissionMemberaep:StateTranscosMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2020-04-012020-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2020-04-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:StateTranscosMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2019-04-012019-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2019-04-012019-06-300000004904us-gaap:ElectricTransmissionMemberaep:StateTranscosMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2020-01-012020-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:StateTranscosMemberaep:OtherRevenuesMemberaep:AEPTransmissionCoMember2020-01-012020-06-300000004904aep:OtherRevenuesMemberaep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2020-01-012020-06-300000004904us-gaap:ElectricTransmissionMemberaep:StateTranscosMemberaep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2019-01-012019-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2019-01-012019-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2020-06-300000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2020-06-300000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2020-06-300000004904aep:StateTranscosMemberaep:AEPTransmissionCoMember2019-12-310000004904aep:AEPTCoParentMemberaep:AEPTransmissionCoMember2019-12-310000004904aep:AEPTransmissionCoMembersrt:ConsolidationEliminationsMember2019-12-31utr:MWh0000004904aep:PowerContractMember2020-06-300000004904aep:PowerContractMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AppalachianPowerCoMemberaep:PowerContractMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:PowerContractMember2020-06-300000004904aep:PowerContractMemberaep:OhioPowerCoMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:PowerContractMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:PowerContractMember2020-06-30utr:MMBTU0000004904aep:NaturalGasContractMember2020-06-300000004904aep:AEPTexasInc.Memberaep:NaturalGasContractMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:NaturalGasContractMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:NaturalGasContractMember2020-06-300000004904aep:OhioPowerCoMemberaep:NaturalGasContractMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:NaturalGasContractMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:NaturalGasContractMember2020-06-30utr:gal0000004904aep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:AEPTexasInc.Memberaep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:OhioPowerCoMemberaep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:HeatingOilAndGasolineContractMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:HeatingOilAndGasolineContractMember2020-06-300000004904us-gaap:InterestRateContractMember2020-06-300000004904aep:AEPTexasInc.Memberus-gaap:InterestRateContractMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:InterestRateContractMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:InterestRateContractMember2020-06-300000004904aep:OhioPowerCoMemberus-gaap:InterestRateContractMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:InterestRateContractMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberus-gaap:InterestRateContractMember2020-06-300000004904aep:InterestRateMember2020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Member2020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMember2020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:InterestRateMemberaep:OhioPowerCoMember2020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMember2020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:PowerContractMember2019-12-310000004904aep:PowerContractMemberaep:AEPTexasInc.Member2019-12-310000004904aep:AppalachianPowerCoMemberaep:PowerContractMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:PowerContractMember2019-12-310000004904aep:PowerContractMemberaep:OhioPowerCoMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:PowerContractMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:PowerContractMember2019-12-310000004904aep:NaturalGasContractMember2019-12-310000004904aep:AEPTexasInc.Memberaep:NaturalGasContractMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:NaturalGasContractMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:NaturalGasContractMember2019-12-310000004904aep:OhioPowerCoMemberaep:NaturalGasContractMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:NaturalGasContractMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:NaturalGasContractMember2019-12-310000004904aep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:AEPTexasInc.Memberaep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:OhioPowerCoMemberaep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:HeatingOilAndGasolineContractMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:HeatingOilAndGasolineContractMember2019-12-310000004904us-gaap:InterestRateContractMember2019-12-310000004904aep:AEPTexasInc.Memberus-gaap:InterestRateContractMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:InterestRateContractMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:InterestRateContractMember2019-12-310000004904aep:OhioPowerCoMemberus-gaap:InterestRateContractMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:InterestRateContractMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberus-gaap:InterestRateContractMember2019-12-310000004904aep:InterestRateMember2019-12-310000004904aep:InterestRateMemberaep:AEPTexasInc.Member2019-12-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMember2019-12-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:InterestRateMemberaep:OhioPowerCoMember2019-12-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMember2019-12-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:CommodityContractMember2020-06-300000004904aep:HedgingContractsMemberus-gaap:CommodityContractMember2020-06-300000004904aep:InterestRateMemberaep:HedgingContractsMember2020-06-300000004904aep:GrossAmountsOfRiskManagementAssetsLiabilitiesRecognizedMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMember2020-06-300000004904aep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:CommodityContractMember2019-12-310000004904aep:HedgingContractsMemberus-gaap:CommodityContractMember2019-12-310000004904aep:InterestRateMemberaep:HedgingContractsMember2019-12-310000004904aep:GrossAmountsOfRiskManagementAssetsLiabilitiesRecognizedMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMember2019-12-310000004904aep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AEPTexasInc.Memberus-gaap:CommodityContractMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AEPTexasInc.Memberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AEPTexasInc.Memberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:AEPTexasInc.Member2019-12-310000004904aep:AEPTexasInc.Memberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:CommodityContractMember2020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMemberaep:HedgingContractsMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:AppalachianPowerCoMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:AppalachianPowerCoMember2019-12-310000004904aep:AppalachianPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CommodityContractMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMemberus-gaap:CommodityContractMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:OhioPowerCoMember2020-06-300000004904aep:OhioPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMemberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:OhioPowerCoMember2019-12-310000004904aep:OhioPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:CommodityContractMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:PublicServiceCoOfOklahomaMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:PublicServiceCoOfOklahomaMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:CommodityContractMember2020-06-300000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:CommodityContractMember2019-12-310000004904aep:GrossAmountsOffsetInStatementOfFinancialPositionMemberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:SouthwesternElectricPowerCoMemberaep:NetAmountsOfAssetsLiabilitiesPresentedInStatementOfFinancialPositionMember2019-12-310000004904aep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-04-012020-06-300000004904aep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-04-012020-06-300000004904aep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-04-012020-06-300000004904aep:PurchasedElectricityForResaleMember2020-04-012020-06-300000004904aep:PurchasedElectricityForResaleMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:PurchasedElectricityForResaleMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:PurchasedElectricityForResaleMember2020-04-012020-06-300000004904aep:PurchasedElectricityForResaleMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:PurchasedElectricityForResaleMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:PurchasedElectricityForResaleMember2020-04-012020-06-300000004904aep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:AEPTexasInc.Memberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:OhioPowerCoMemberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherOperationExpenseMember2020-04-012020-06-300000004904aep:MaintenanceExpenseMember2020-04-012020-06-300000004904aep:MaintenanceExpenseMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:MaintenanceExpenseMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:MaintenanceExpenseMember2020-04-012020-06-300000004904aep:MaintenanceExpenseMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:MaintenanceExpenseMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:MaintenanceExpenseMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:AppalachianPowerCoMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:PublicServiceCoOfOklahomaMember2020-04-012020-06-300000004904aep:RegulatoryAssetsMemberaep:SouthwesternElectricPowerCoMember2020-04-012020-06-300000004904aep:RegulatoryLiabilitiesMember2020-04-012020-06-300000004904aep:RegulatoryLiabilitiesMemberaep:AEPTexasInc.Member2020-04-012020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryLiabilitiesMember2020-04-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryLiabilitiesMember2020-04-012020-06-300000004904aep:RegulatoryLiabilitiesMemberaep:OhioPowerCoMember2020-04-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryLiabilitiesMember2020-04-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryLiabilitiesMember2020-04-012020-06-300000004904aep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-04-012019-06-300000004904aep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-04-012019-06-300000004904aep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-04-012019-06-300000004904aep:PurchasedElectricityForResaleMember2019-04-012019-06-300000004904aep:PurchasedElectricityForResaleMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:PurchasedElectricityForResaleMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:PurchasedElectricityForResaleMember2019-04-012019-06-300000004904aep:PurchasedElectricityForResaleMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:PurchasedElectricityForResaleMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:PurchasedElectricityForResaleMember2019-04-012019-06-300000004904aep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:AEPTexasInc.Memberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:OhioPowerCoMemberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherOperationExpenseMember2019-04-012019-06-300000004904aep:MaintenanceExpenseMember2019-04-012019-06-300000004904aep:MaintenanceExpenseMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:MaintenanceExpenseMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:MaintenanceExpenseMember2019-04-012019-06-300000004904aep:MaintenanceExpenseMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:MaintenanceExpenseMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:MaintenanceExpenseMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:AppalachianPowerCoMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:PublicServiceCoOfOklahomaMember2019-04-012019-06-300000004904aep:RegulatoryAssetsMemberaep:SouthwesternElectricPowerCoMember2019-04-012019-06-300000004904aep:RegulatoryLiabilitiesMember2019-04-012019-06-300000004904aep:RegulatoryLiabilitiesMemberaep:AEPTexasInc.Member2019-04-012019-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryLiabilitiesMember2019-04-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryLiabilitiesMember2019-04-012019-06-300000004904aep:RegulatoryLiabilitiesMemberaep:OhioPowerCoMember2019-04-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryLiabilitiesMember2019-04-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryLiabilitiesMember2019-04-012019-06-300000004904aep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:OhioPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2020-01-012020-06-300000004904aep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:OhioPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:GenerationAndMarketingRevenuesMember2020-01-012020-06-300000004904aep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:OhioPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2020-01-012020-06-300000004904aep:PurchasedElectricityForResaleMember2020-01-012020-06-300000004904aep:PurchasedElectricityForResaleMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:PurchasedElectricityForResaleMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:PurchasedElectricityForResaleMember2020-01-012020-06-300000004904aep:PurchasedElectricityForResaleMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:PurchasedElectricityForResaleMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:PurchasedElectricityForResaleMember2020-01-012020-06-300000004904aep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:AEPTexasInc.Memberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:OhioPowerCoMemberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherOperationExpenseMember2020-01-012020-06-300000004904aep:MaintenanceExpenseMember2020-01-012020-06-300000004904aep:MaintenanceExpenseMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:MaintenanceExpenseMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:MaintenanceExpenseMember2020-01-012020-06-300000004904aep:MaintenanceExpenseMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:MaintenanceExpenseMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:MaintenanceExpenseMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:AppalachianPowerCoMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:PublicServiceCoOfOklahomaMember2020-01-012020-06-300000004904aep:RegulatoryAssetsMemberaep:SouthwesternElectricPowerCoMember2020-01-012020-06-300000004904aep:RegulatoryLiabilitiesMember2020-01-012020-06-300000004904aep:RegulatoryLiabilitiesMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryLiabilitiesMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryLiabilitiesMember2020-01-012020-06-300000004904aep:RegulatoryLiabilitiesMemberaep:OhioPowerCoMember2020-01-012020-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryLiabilitiesMember2020-01-012020-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryLiabilitiesMember2020-01-012020-06-300000004904aep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:OhioPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:VerticallyIntegratedUtilitiesRevenuesMember2019-01-012019-06-300000004904aep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:OhioPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:GenerationAndMarketingRevenuesMember2019-01-012019-06-300000004904aep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:OhioPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:ElectricGenerationTransmissionDistributionRevenuesMember2019-01-012019-06-300000004904aep:PurchasedElectricityForResaleMember2019-01-012019-06-300000004904aep:PurchasedElectricityForResaleMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:PurchasedElectricityForResaleMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:PurchasedElectricityForResaleMember2019-01-012019-06-300000004904aep:PurchasedElectricityForResaleMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:PurchasedElectricityForResaleMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:PurchasedElectricityForResaleMember2019-01-012019-06-300000004904aep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:AEPTexasInc.Memberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:OhioPowerCoMemberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:OtherOperationExpenseMember2019-01-012019-06-300000004904aep:MaintenanceExpenseMember2019-01-012019-06-300000004904aep:MaintenanceExpenseMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:MaintenanceExpenseMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:MaintenanceExpenseMember2019-01-012019-06-300000004904aep:MaintenanceExpenseMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:MaintenanceExpenseMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:MaintenanceExpenseMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:AppalachianPowerCoMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:PublicServiceCoOfOklahomaMember2019-01-012019-06-300000004904aep:RegulatoryAssetsMemberaep:SouthwesternElectricPowerCoMember2019-01-012019-06-300000004904aep:RegulatoryLiabilitiesMember2019-01-012019-06-300000004904aep:RegulatoryLiabilitiesMemberaep:AEPTexasInc.Member2019-01-012019-06-300000004904aep:AppalachianPowerCoMemberaep:RegulatoryLiabilitiesMember2019-01-012019-06-300000004904aep:IndianaMichiganPowerCoMemberaep:RegulatoryLiabilitiesMember2019-01-012019-06-300000004904aep:RegulatoryLiabilitiesMemberaep:OhioPowerCoMember2019-01-012019-06-300000004904aep:PublicServiceCoOfOklahomaMemberaep:RegulatoryLiabilitiesMember2019-01-012019-06-300000004904aep:SouthwesternElectricPowerCoMemberaep:RegulatoryLiabilitiesMember2019-01-012019-06-300000004904us-gaap:CommodityContractMember2020-06-300000004904us-gaap:CommodityContractMember2019-12-310000004904us-gaap:CommodityContractMember2020-01-012020-06-300000004904aep:InterestRateMember2020-01-012020-06-300000004904us-gaap:CommodityContractMember2019-01-012019-12-310000004904aep:InterestRateMember2019-01-012019-12-310000004904aep:InterestRateMemberaep:AEPTexasInc.Member2020-01-012020-06-300000004904aep:InterestRateMemberaep:AEPTexasInc.Member2019-01-012019-12-310000004904aep:InterestRateMemberaep:AppalachianPowerCoMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:AppalachianPowerCoMember2019-01-012019-12-310000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:IndianaMichiganPowerCoMember2019-01-012019-12-310000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:PublicServiceCoOfOklahomaMember2019-01-012019-12-310000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMember2020-01-012020-06-300000004904aep:InterestRateMemberaep:SouthwesternElectricPowerCoMember2019-01-012019-12-310000004904aep:EquityunitsMember2020-06-300000004904aep:EquityunitsMember2019-12-310000004904us-gaap:CashMember2020-06-300000004904aep:MutualFundsFixedIncomeMember2020-06-300000004904us-gaap:MutualFundMember2020-06-300000004904us-gaap:CashMember2019-12-310000004904aep:MutualFundsFixedIncomeMember2019-12-310000004904us-gaap:MutualFundMember2019-12-310000004904us-gaap:CashAndCashEquivalentsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:CashAndCashEquivalentsMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2020-01-012020-06-300000004904us-gaap:CashAndCashEquivalentsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:CashAndCashEquivalentsMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2019-01-012019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMember2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:SpentNuclearFuelandDecommissioningTrustsMember2020-01-012020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMember2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:SpentNuclearFuelandDecommissioningTrustsMember2019-01-012019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2019-01-012019-12-310000004904us-gaap:CorporateDebtSecuritiesMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:CorporateDebtSecuritiesMember2020-01-012020-06-300000004904us-gaap:CorporateDebtSecuritiesMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:CorporateDebtSecuritiesMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2019-01-012019-12-310000004904us-gaap:StateAndLocalJurisdictionMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:StateAndLocalJurisdictionMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2020-01-012020-06-300000004904us-gaap:StateAndLocalJurisdictionMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:StateAndLocalJurisdictionMember2019-01-012019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:FixedIncomeFundsMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:FixedIncomeFundsMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:FixedIncomeFundsMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberus-gaap:FixedIncomeFundsMember2019-01-012019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:DomesticMember2020-06-300000004904aep:DomesticMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:DomesticMember2020-01-012020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:DomesticMember2019-12-310000004904aep:DomesticMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:DomesticMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2020-01-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2019-01-012019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2020-04-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2020-04-012020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2019-04-012019-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2019-04-012019-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2019-01-012019-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2019-01-012019-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:SpentNuclearFuelandDecommissioningTrustsMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:SpentNuclearFuelandDecommissioningTrustsMember2019-12-310000004904us-gaap:CashMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CashMember2020-06-300000004904us-gaap:CashMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CashMember2020-06-300000004904aep:MutualFundsFixedIncomeMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:MutualFundsFixedIncomeMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:MutualFundsFixedIncomeMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:MutualFundsFixedIncomeMember2020-06-300000004904us-gaap:MutualFundMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:MutualFundMember2020-06-300000004904us-gaap:MutualFundMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:MutualFundMember2020-06-300000004904us-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Member2020-06-300000004904us-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904aep:RiskManagementCommodityContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel1Memberus-gaap:CommodityMember2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CommodityMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CommodityMember2020-06-300000004904us-gaap:CommodityMember2020-06-300000004904us-gaap:FairValueInputsLevel1Memberaep:InterestRateMember2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:InterestRateMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:InterestRateMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:InterestRateMember2020-06-300000004904aep:InterestRateMember2020-06-300000004904us-gaap:CashAndCashEquivalentsMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel2Member2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904us-gaap:CorporateDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904us-gaap:StateAndLocalJurisdictionMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904us-gaap:FairValueInputsLevel1Memberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:FairValueInputsLevel2Memberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:FixedIncomeFundsMember2020-06-300000004904aep:DomesticMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:DomesticMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:DomesticMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:DomesticMember2020-06-300000004904us-gaap:CashMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CashMember2019-12-310000004904us-gaap:CashMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CashMember2019-12-310000004904aep:MutualFundsFixedIncomeMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:MutualFundsFixedIncomeMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:MutualFundsFixedIncomeMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:MutualFundsFixedIncomeMember2019-12-310000004904us-gaap:MutualFundMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:MutualFundMember2019-12-310000004904us-gaap:MutualFundMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:MutualFundMember2019-12-310000004904us-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Member2019-12-310000004904us-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904aep:RiskManagementCommodityContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel1Memberus-gaap:CommodityMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CommodityMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CommodityMember2019-12-310000004904us-gaap:CommodityMember2019-12-310000004904us-gaap:FairValueInputsLevel1Memberaep:InterestRateMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:InterestRateMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:InterestRateMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:InterestRateMember2019-12-310000004904aep:InterestRateMember2019-12-310000004904us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueHedgingMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueHedgingMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueHedgingMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:FairValueHedgingMember2019-12-310000004904us-gaap:FairValueHedgingMember2019-12-310000004904us-gaap:CashAndCashEquivalentsMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel2Member2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904us-gaap:CorporateDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904us-gaap:StateAndLocalJurisdictionMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904us-gaap:FairValueInputsLevel1Memberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberus-gaap:FixedIncomeFundsMember2019-12-310000004904aep:DomesticMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:DomesticMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:DomesticMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:DomesticMember2019-12-310000004904aep:AEPTexasInc.Memberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:AEPTexasInc.Member2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:AEPTexasInc.Member2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:AEPTexasInc.Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AEPTexasInc.Memberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:AEPTexasInc.Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel3Memberaep:AEPTexasInc.Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:AEPTexasInc.Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AEPTexasInc.Member2020-06-300000004904aep:AEPTexasInc.Memberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:AEPTexasInc.Member2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:AEPTexasInc.Member2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:AEPTexasInc.Member2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel2Member2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel2Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel1Memberaep:InterestRateMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel2Memberaep:InterestRateMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:InterestRateMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:InterestRateMember2020-06-300000004904aep:AppalachianPowerCoMemberaep:InterestRateMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel2Member2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel2Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:AppalachianPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FixedIncomeFundsMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberaep:DomesticMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:DomesticMember2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:CashAndCashEquivalentsMember2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberaep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:USGovernmentAgenciesDebtSecuritiesMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:CorporateDebtSecuritiesMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:StateAndLocalJurisdictionMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FixedIncomeFundsMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberus-gaap:FixedIncomeFundsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberaep:DomesticMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:DomesticMember2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMemberaep:DomesticMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:IndianaMichiganPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:OhioPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:OhioPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:OhioPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:OhioPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:OhioPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel2Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel2Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:PublicServiceCoOfOklahomaMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:FairValueInputsLevel1Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMember2020-06-300000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:FairValueInputsLevel1Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:FairValueInputsLevel2Memberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:RiskManagementCommodityContractsMemberus-gaap:PortionAtOtherThanFairValueFairValueDisclosureMemberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:RiskManagementCommodityContractsMemberaep:SouthwesternElectricPowerCoMember2019-12-310000004904aep:MaturityPeriod2Memberus-gaap:FairValueInputsLevel1Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:WithinCurrentYearMember2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:MaturityPeriod2Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:MaturityPeriod3Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:MaturityPeriodFourMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:WithinCurrentYearMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:MaturityPeriod2Member2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:MaturityPeriod3Member2020-06-300000004904aep:MaturityPeriodFourMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904us-gaap:FairValueInputsLevel2Memberaep:WithinCurrentYearMember2019-12-310000004904us-gaap:FairValueInputsLevel2Memberaep:MaturityPeriod2Member2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:WithinCurrentYearMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:MaturityPeriod2Member2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:MaturityPeriod3Member2019-12-310000004904aep:MaturityPeriodFourMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2020-06-300000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Member2020-06-300000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMember2020-06-300000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMember2020-06-300000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2019-12-310000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Member2019-12-310000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMember2019-12-310000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMember2019-12-310000004904aep:NaturalGasContractMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2020-06-300000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2019-12-310000004904aep:AppalachianPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2020-06-300000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:EnergyContractsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMemberaep:EnergyContractsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:MaximumMemberaep:EnergyContractsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Membersrt:WeightedAverageMemberaep:EnergyContractsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2019-12-310000004904aep:IndianaMichiganPowerCoMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:MinimumMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:MaximumMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:WeightedAverageMemberaep:EnergyContractsMember2020-06-300000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMemberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:MinimumMemberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:MaximumMemberaep:EnergyContractsMember2019-12-310000004904us-gaap:FairValueInputsLevel3Memberaep:OhioPowerCoMembersrt:WeightedAverageMemberaep:EnergyContractsMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MaximumMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:WeightedAverageMember2020-06-300000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMemberus-gaap:FairValueInputsLevel3Memberaep:FinancialTrasnsmissionRightsMembersrt:MinimumMember2019-12-310000004904aep:PublicServiceCoOfOklahomaMember