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Fair Value Long-term Debt, Other Temporary Investments, Nuclear Trusts (Details) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding $ 18,684,000,000us-gaap_LongTermDebt $ 18,377,000,000us-gaap_LongTermDebt  
Long-term Debt, Fair Value 21,075,000,000us-gaap_LongTermDebtFairValue 19,672,000,000us-gaap_LongTermDebtFairValue  
Other Temporary Investments      
Cost 374,000,000us-gaap_InvestmentOwnedAtCost 342,000,000us-gaap_InvestmentOwnedAtCost  
Gross Unrealized Gains 12,000,000us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation 11,000,000us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation  
Gross Unrealized Losses 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation  
Estimated Fair Value 386,000,000us-gaap_ShortTermInvestments 353,000,000us-gaap_ShortTermInvestments  
Debt and Equity Securities Within Other Temporary Investments [Abstract]      
Proceeds From Investment Sales 0us-gaap_ProceedsFromSaleOfShortTermInvestments 0us-gaap_ProceedsFromSaleOfShortTermInvestments 0us-gaap_ProceedsFromSaleOfShortTermInvestments
Purchases of Investments 2,000,000us-gaap_PaymentsToAcquireShortTermInvestments 17,000,000us-gaap_PaymentsToAcquireShortTermInvestments 2,000,000us-gaap_PaymentsToAcquireShortTermInvestments
Gross Realized Gains on Investment Sales 0aep_GrossRealizedGainsOnInvestmentSalesOnShortTermInvestment 0aep_GrossRealizedGainsOnInvestmentSalesOnShortTermInvestment 0aep_GrossRealizedGainsOnInvestmentSalesOnShortTermInvestment
Gross Realized Losses on Investment Sales 0aep_GrossRealizedLossesOnInvestmentSalesOnShortTermInvestment 0aep_GrossRealizedLossesOnInvestmentSalesOnShortTermInvestment 0aep_GrossRealizedLossesOnInvestmentSalesOnShortTermInvestment
Nuclear Trust Fund Investments      
Estimated Fair Value 2,096,000,000aep_SpentNuclearFuelAndDecommissioningTrusts 1,932,000,000aep_SpentNuclearFuelAndDecommissioningTrusts  
Gross Unrealized Gains 649,000,000aep_GrossUnrealizedGains 535,000,000aep_GrossUnrealizedGains  
Other-Than-Temporary Impairments (85,000,000)aep_TemporaryImpairments (87,000,000)aep_TemporaryImpairments  
Securities Activity Within the Decommissioning and SNF Trusts      
Proceeds from Investment Sales 1,032,000,000aep_ProceedsFromInvestmentSales 858,000,000aep_ProceedsFromInvestmentSales 988,000,000aep_ProceedsFromInvestmentSales
Purchases of Investments 1,086,000,000aep_PurchasesOfInvestments 910,000,000aep_PurchasesOfInvestments 1,045,000,000aep_PurchasesOfInvestments
Gross Realized Gains on Investment Sales 32,000,000aep_GrossRealizedGainsOnInvestmentSales 18,000,000aep_GrossRealizedGainsOnInvestmentSales 25,000,000aep_GrossRealizedGainsOnInvestmentSales
Gross Realized Losses on Investment Sales 15,000,000aep_GrossRealizedLossesOnInvestmentSales 8,000,000aep_GrossRealizedLossesOnInvestmentSales 9,000,000aep_GrossRealizedLossesOnInvestmentSales
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 2,096,000,000aep_SpentNuclearFuelAndDecommissioningTrusts 1,932,000,000aep_SpentNuclearFuelAndDecommissioningTrusts  
Fair Value Measurements (Textuals) [Abstract]      
Adjusted Cost of Debt Securities 903,000,000aep_AdjustedCostOfDebtSecurities 872,000,000aep_AdjustedCostOfDebtSecurities  
Adjusted Cost of Domestic Equity Securities 524,000,000aep_AdjustedCostOfEquitySecurities 506,000,000aep_AdjustedCostOfEquitySecurities  
Appalachian Power Co [Member]      
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding 3,980,274,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_AppalachianPowerCoMember		 4,194,357,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_AppalachianPowerCoMember		  
Long-term Debt, Fair Value 4,711,210,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_AppalachianPowerCoMember		 4,587,079,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_AppalachianPowerCoMember		  
Indiana Michigan Power Co [Member]      
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding 2,027,397,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 2,039,016,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Long-term Debt, Fair Value 2,255,124,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 2,174,891,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Nuclear Trust Fund Investments      
Estimated Fair Value 2,095,732,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 1,931,610,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Gross Unrealized Gains 649,132,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 534,850,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Other-Than-Temporary Impairments (85,495,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 (86,994,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Securities Activity Within the Decommissioning and SNF Trusts      
Proceeds from Investment Sales 1,031,793,000aep_ProceedsFromInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 858,406,000aep_ProceedsFromInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 987,550,000aep_ProceedsFromInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
Purchases of Investments 1,086,437,000aep_PurchasesOfInvestments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 909,998,000aep_PurchasesOfInvestments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 1,045,422,000aep_PurchasesOfInvestments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
Gross Realized Gains on Investment Sales 32,305,000aep_GrossRealizedGainsOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 18,326,000aep_GrossRealizedGainsOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 24,605,000aep_GrossRealizedGainsOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
Gross Realized Losses on Investment Sales 15,410,000aep_GrossRealizedLossesOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 8,108,000aep_GrossRealizedLossesOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 8,881,000aep_GrossRealizedLossesOnInvestmentSales
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 2,095,732,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 1,931,610,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Fair Value Measurements (Textuals) [Abstract]      
Adjusted Cost of Debt Securities 903,000,000aep_AdjustedCostOfDebtSecurities
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 872,000,000aep_AdjustedCostOfDebtSecurities
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Adjusted Cost of Domestic Equity Securities 524,000,000aep_AdjustedCostOfEquitySecurities
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		 506,000,000aep_AdjustedCostOfEquitySecurities
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		  
Ohio Power Co [Member]      
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding 2,297,123,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_OhioPowerCoMember		 2,735,175,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_OhioPowerCoMember		  
Long-term Debt, Fair Value 2,709,452,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_OhioPowerCoMember		 3,007,191,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_OhioPowerCoMember		  
Public Service Co Of Oklahoma [Member]      
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding 1,041,036,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_PublicServiceCoOfOklahomaMember		 999,810,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_PublicServiceCoOfOklahomaMember		  
Long-term Debt, Fair Value 1,216,205,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_PublicServiceCoOfOklahomaMember		 1,111,149,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_PublicServiceCoOfOklahomaMember		  
Southwestern Electric Power Co [Member]      
Book Values and Fair Values of Long - term Debt      
Total Long-term Debt Outstanding 2,140,437,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_SouthwesternElectricPowerCoMember		 2,043,332,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= aep_SouthwesternElectricPowerCoMember		  
Long-term Debt, Fair Value 2,402,639,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_SouthwesternElectricPowerCoMember		 2,214,730,000us-gaap_LongTermDebtFairValue
/ dei_LegalEntityAxis
= aep_SouthwesternElectricPowerCoMember		  
Cash [Member]      
Other Temporary Investments      
Cost 280,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 250,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		  
Gross Unrealized Gains 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		  
Gross Unrealized Losses 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		  
Estimated Fair Value 280,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [1] 250,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [1]  
Nuclear Trust Fund Investments      
Estimated Fair Value 20,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [2] 19,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [2]  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 20,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [2] 19,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [2]  
Cash [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 19,966,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [3] 18,804,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [3]  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 19,966,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [3] 18,804,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashMember		 [3]  
Fixed Income Funds [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 953,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 901,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Gross Unrealized Gains 50,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 29,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Other-Than-Temporary Impairments (6,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 (5,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 953,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 901,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Fixed Income Funds [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 953,387,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 900,295,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Gross Unrealized Gains 50,344,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 29,312,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Other-Than-Temporary Impairments (6,353,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 (5,317,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 953,387,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		 900,295,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedIncomeFundsMember		  
Mutual Funds Fixed Income [Member]      
Other Temporary Investments      
Cost 81,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		 80,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		  
Gross Unrealized Gains 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		  
Gross Unrealized Losses 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		  
Estimated Fair Value 81,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		 80,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsFixedIncomeMember		  
Domestic [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 1,123,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4] 1,012,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4]  
Gross Unrealized Gains 599,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 506,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		  
Other-Than-Temporary Impairments (79,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 (82,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 1,123,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4] 1,012,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4]  
Domestic [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 1,122,379,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4] 1,012,511,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4]  
Gross Unrealized Gains 598,788,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 505,538,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		  
Other-Than-Temporary Impairments (79,142,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 (81,677,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 1,122,379,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4] 1,012,511,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_DomesticMember		 [4]  
Mutual Funds Equity [Member]      
Other Temporary Investments      
Cost 13,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		 12,000,000us-gaap_InvestmentOwnedAtCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		  
Gross Unrealized Gains 12,000,000us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		 11,000,000us-gaap_InvestmentOwnedUnrecognizedUnrealizedAppreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		  
Gross Unrealized Losses 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		 0us-gaap_InvestmentOwnedUnrecognizedUnrealizedDepreciation
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		  
Estimated Fair Value 25,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		 [4] 23,000,000us-gaap_ShortTermInvestments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= aep_MutualFundsEquityMember		 [4]  
Cash and Cash Equivalents [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 20,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 19,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Gross Unrealized Gains 0aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 0aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Other-Than-Temporary Impairments 0aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 0aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 20,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 19,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Cash and Cash Equivalents [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 19,966,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 18,804,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Gross Unrealized Gains 0aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 0aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Other-Than-Temporary Impairments 0aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 0aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 19,966,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		 18,804,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CashAndCashEquivalentsMember		  
US Government Agencies Debt Securities [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 697,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 609,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Gross Unrealized Gains 45,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 26,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Other-Than-Temporary Impairments (5,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 (4,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 697,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 609,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
US Government Agencies Debt Securities [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 697,042,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 608,875,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Gross Unrealized Gains 44,615,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 26,114,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Other-Than-Temporary Impairments (5,016,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 (3,824,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 697,042,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		 608,875,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember		  
Corporate Debt Securities [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 48,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 37,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Gross Unrealized Gains 4,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 2,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Other-Than-Temporary Impairments (1,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 (1,000,000)aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 48,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 37,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Corporate Debt Securities [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 47,792,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 36,782,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Gross Unrealized Gains 4,523,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 2,450,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Other-Than-Temporary Impairments (1,018,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 (1,123,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 47,792,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		 36,782,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember		  
State and Local Jurisdiction [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 208,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 255,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Gross Unrealized Gains 1,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 1,000,000aep_GrossUnrealizedGains
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Other-Than-Temporary Impairments 0aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 0aep_TemporaryImpairments
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 208,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 255,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
State and Local Jurisdiction [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 208,553,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 254,638,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Gross Unrealized Gains 1,206,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 748,000aep_GrossUnrealizedGains
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Other-Than-Temporary Impairments (319,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 (370,000)aep_TemporaryImpairments
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 208,553,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		 254,638,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_StateAndLocalJurisdictionMember		  
Within One Year [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 154,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_WithinOneYearMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 154,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_WithinOneYearMember		    
Within One Year [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 154,447,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_WithinOneYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 154,447,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_WithinOneYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
One Year To Five Year [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 376,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_OneYearToFiveYearMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 376,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_OneYearToFiveYearMember		    
One Year To Five Year [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 376,291,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_OneYearToFiveYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 376,291,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_OneYearToFiveYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
Five Year To Ten Year [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 179,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_FiveYearToTenYearMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 179,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_FiveYearToTenYearMember		    
Five Year To Ten Year [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 178,436,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_FiveYearToTenYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 178,436,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_FiveYearToTenYearMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
After 10 years [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 244,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_After10YearsMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities 244,000,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_After10YearsMember		    
After 10 years [Member] | Indiana Michigan Power Co [Member]      
Nuclear Trust Fund Investments      
Estimated Fair Value 244,213,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_After10YearsMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
Contractual Maturities, Fair Value of Debt Securities      
Contractual Maturities, Fair Value of Debt Securities $ 244,213,000aep_SpentNuclearFuelAndDecommissioningTrusts
/ aep_ContractualMaturitiesYearAxis
= aep_After10YearsMember
/ dei_LegalEntityAxis
= aep_IndianaMichiganPowerCoMember		    
[1] Amounts in "Other" column primarily represent cash deposits in bank accounts with financial institutions or with third parties. Level 1 and Level 2 amounts primarily represent investments in money market funds.
[2] Amounts in "Other" column primarily represent accrued interest receivables from financial institutions. Level 1 amounts primarily represent investments in money market funds.
[3] Amounts in “Other” column primarily represent accrued interest receivables from financial institutions. Level 1 amounts primarily represent investments in money market funds.
[4] Amounts represent publicly traded equity securities and equity-based mutual funds.