v3.24.0.1
Derivatives and Hedging (Details)
gal in Millions, MWh in Millions, MMBTU in Millions
 12 Months Ended
Dec. 31, 2023
USD ($)
MWh
MMBTU
gal
Dec. 31, 2022
USD ($)
MMBTU
MWh
gal
Dec. 31, 2021
USD ($)
Cash Collateral Netting      
Cash Collateral Received Netted Against Risk Management Assets $ 46,000,000 $ 481,000,000  
Fair Value of Derivative Instruments      
Current Risk Management Assets 217,500,000 348,800,000  
Derivative Asset, Noncurrent 321,200,000 284,100,000  
Total Assets 538,700,000 632,900,000  
Current Risk Management Liabilities 229,600,000 145,200,000  
Derivative Liability, Noncurrent 241,800,000 345,200,000  
Total Liabilities 471,400,000 490,400,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (322,800,000) 693,700,000 $ 324,000,000.0
Impact of Fair Value Hedges on the Balance Sheet      
Carrying Amount of Hedged Asset (Liability) [1],[2] (878,200,000) (855,500,000)  
Cumulative Fair Value Hedging Adjustment in the Carrying Amount of the Hedged Asset (Liability) [1],[2] 68,400,000 89,700,000  
Gain (Loss) on Hedging Instruments      
Gain (Loss) on Fair Value Instruments [3] 29,000,000.0 (90,400,000) (35,500,000)
Gain (Loss) on Fair Value Portion of Long Term Debt [3] (29,000,000.0) 90,400,000 35,500,000
Collateral Triggering Events      
Fair Value Of Derivative Liabilities Subject To Cross Acceleration Provisions 107,000,000 127,000,000  
Liabilities for Contracts with Cross Default Provisions Prior to Contractural Netting Arrangements 242,000,000 217,000,000  
Derivatives and Hedging (Textuals)      
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) (30,000,000) (38,000,000)  
Credit Downgrade Trigger Exposure 0 2,000,000  
AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Total Liabilities 2,700,000    
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (600,000) 2,800,000 2,000,000.0
Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 22,400,000 69,100,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (18,600,000) 88,600,000 55,300,000
Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 27,800,000 15,200,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 29,200,000 19,600,000 (18,200,000)
Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Liabilities 6,800,000 1,800,000  
Derivative Liability, Noncurrent 43,900,000 37,900,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (14,100,000) 57,800,000 11,100,000
Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 19,000,000.0 25,300,000  
Current Risk Management Liabilities 28,900,000 1,600,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 58,800,000 103,700,000 46,000,000.0
Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 11,600,000 16,400,000  
Current Risk Management Liabilities 14,400,000 1,400,000  
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 55,000,000.0 77,700,000 41,500,000
Risk Management Contracts [Member]      
Fair Value of Derivative Instruments      
Total Assets [5] 403,900,000 [4] 315,400,000 [6]  
Total Liabilities [5] 362,300,000 [4] 339,800,000 [6]  
Risk Management Contracts [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Total Liabilities [5] 0    
Risk Management Contracts [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Total Assets [5] 22,400,000 69,100,000  
Total Liabilities [5] 22,500,000 3,500,000  
Risk Management Contracts [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Total Assets [5] 39,600,000 15,400,000  
Total Liabilities [5] 2,000,000.0 0  
Risk Management Contracts [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Total Liabilities [5] 50,700,000 39,700,000  
Risk Management Contracts [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Total Assets [5] 19,000,000.0 25,300,000  
Total Liabilities [5] 29,900,000 1,600,000  
Risk Management Contracts [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Total Assets [5] 11,600,000 16,400,000  
Total Liabilities [5] 15,600,000 1,400,000  
Commodity [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 104,900,000 223,500,000  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months $ 38,300,000 119,900,000  
Derivatives and Hedging (Textuals)      
Maximum Length of Time Hedged in Price Risk Cash Flow Hedge 87 months    
Cross Default Provisions Maximum Third Party Obligation Amount $ 50,000,000    
Cross Acceleration Provisions Maximum Third Party Obligation Amount 50,000,000    
Commodity [Member] | AEP Texas Inc. [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 0 0  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 0  
Commodity [Member] | Appalachian Power Co [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 0 0  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 0  
Commodity [Member] | Indiana Michigan Power Co [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 0 0  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 0  
Commodity [Member] | Public Service Co Of Oklahoma [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 0 0  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 0  
Commodity [Member] | Southwestern Electric Power Co [Member]      
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 0 0  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 0  
Commodity [Member] | Risk Management Contracts [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 555,100,000 965,400,000  
Derivative Asset, Noncurrent 468,800,000 565,600,000  
Current Risk Management Liabilities 588,000,000.0 663,800,000  
Derivative Liability, Noncurrent 377,600,000 412,000,000.0  
Commodity [Member] | Risk Management Contracts [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 200,000 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Risk Management Contracts [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 24,600,000 69,300,000  
Derivative Asset, Noncurrent 300,000 700,000  
Current Risk Management Liabilities 18,500,000 4,100,000  
Derivative Liability, Noncurrent 6,900,000 700,000  
Commodity [Member] | Risk Management Contracts [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 30,100,000 16,000,000.0  
Derivative Asset, Noncurrent 12,000,000.0 500,000  
Current Risk Management Liabilities 5,400,000 900,000  
Derivative Liability, Noncurrent 200,000 300,000  
Commodity [Member] | Risk Management Contracts [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 6,900,000 2,100,000  
Derivative Liability, Noncurrent 43,900,000 37,900,000  
Commodity [Member] | Risk Management Contracts [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 19,700,000 24,100,000  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 29,700,000 2,100,000  
Derivative Liability, Noncurrent 1,000,000.0 0  
Commodity [Member] | Risk Management Contracts [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 12,000,000.0 16,800,000  
Derivative Asset, Noncurrent 500,000 0  
Current Risk Management Liabilities 14,900,000 2,000,000.0  
Derivative Liability, Noncurrent 1,700,000 0  
Commodity [Member] | Hedging Contracts [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 56,700,000 212,200,000  
Derivative Asset, Noncurrent 86,800,000 148,900,000  
Current Risk Management Liabilities 8,200,000 60,400,000  
Derivative Liability, Noncurrent 2,200,000 17,400,000  
Commodity [Member] | Hedging Contracts [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Hedging Contracts [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Hedging Contracts [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Hedging Contracts [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Hedging Contracts [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Commodity [Member] | Hedging Contracts [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member]      
Commodity      
Derivative, Notional Amount 1,300,000,000 1,650,000,000  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax (8,100,000) 300,000  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 3,200,000 300,000  
Interest Rate [Member] | AEP Texas Inc. [Member]      
Commodity      
Derivative, Notional Amount 150,000,000.0 0  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 500,000 (300,000)  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 200,000 (200,000)  
Interest Rate [Member] | Appalachian Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 5,900,000 6,700,000  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 800,000 800,000  
Interest Rate [Member] | Indiana Michigan Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax (5,500,000) (5,100,000)  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months (400,000) (600,000)  
Interest Rate [Member] | Ohio Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate [Member] | Public Service Co Of Oklahoma [Member]      
Commodity      
Derivative, Notional Amount 0 200,000,000.0  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax (200,000) 1,300,000  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 0 100,000  
Interest Rate [Member] | Southwestern Electric Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Impact of Cash Flow Hedges on the Balance Sheet      
AOCI Gain (Loss) Net of Tax 1,300,000 1,100,000  
Portion Expected to be Reclassified to Net Income During the Next Twelve Months 300,000 200,000  
Interest Rate [Member] | Hedging Contracts [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 1,800,000  
Derivative Asset, Noncurrent 0 14,300,000  
Current Risk Management Liabilities 50,500,000 41,400,000  
Derivative Liability, Noncurrent 56,900,000 91,100,000  
Interest Rate [Member] | Hedging Contracts [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 2,700,000 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member] | Hedging Contracts [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member] | Hedging Contracts [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member] | Hedging Contracts [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member] | Hedging Contracts [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 1,600,000  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Interest Rate [Member] | Hedging Contracts [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities 0 0  
Derivative Liability, Noncurrent 0 0  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 611,800,000 1,179,400,000  
Derivative Asset, Noncurrent 555,600,000 728,800,000  
Total Assets 1,167,400,000 1,908,200,000  
Current Risk Management Liabilities 646,700,000 765,600,000  
Derivative Liability, Noncurrent 436,700,000 520,500,000  
Total Liabilities 1,083,400,000 1,286,100,000  
Total MTM Derivative Contract Net Assets (Liabilities) 84,000,000.0 622,100,000  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Total Assets 0 0  
Current Risk Management Liabilities 2,900,000 0  
Derivative Liability, Noncurrent 0 0  
Total Liabilities 2,900,000 0  
Total MTM Derivative Contract Net Assets (Liabilities) (2,900,000) 0  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 24,600,000 69,300,000  
Derivative Asset, Noncurrent 300,000 700,000  
Total Assets 24,900,000 70,000,000.0  
Current Risk Management Liabilities 18,500,000 4,100,000  
Derivative Liability, Noncurrent 6,900,000 700,000  
Total Liabilities 25,400,000 4,800,000  
Total MTM Derivative Contract Net Assets (Liabilities) (500,000) 65,200,000  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 30,100,000 16,000,000.0  
Derivative Asset, Noncurrent 12,000,000.0 500,000  
Total Assets 42,100,000 16,500,000  
Current Risk Management Liabilities 5,400,000 900,000  
Derivative Liability, Noncurrent 200,000 300,000  
Total Liabilities 5,600,000 1,200,000  
Total MTM Derivative Contract Net Assets (Liabilities) 36,500,000 15,300,000  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Total Assets 0 0  
Current Risk Management Liabilities 6,900,000 2,100,000  
Derivative Liability, Noncurrent 43,900,000 37,900,000  
Total Liabilities 50,800,000 40,000,000.0  
Total MTM Derivative Contract Net Assets (Liabilities) (50,800,000) (40,000,000.0)  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 19,700,000 25,700,000  
Derivative Asset, Noncurrent 0 0  
Total Assets 19,700,000 25,700,000  
Current Risk Management Liabilities 29,700,000 2,100,000  
Derivative Liability, Noncurrent 1,000,000.0 0  
Total Liabilities 30,700,000 2,100,000  
Total MTM Derivative Contract Net Assets (Liabilities) (11,000,000.0) 23,600,000  
Gross Amounts of Risk Management Assets/Liabilities Recognized [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 12,000,000.0 16,800,000  
Derivative Asset, Noncurrent 500,000 0  
Total Assets 12,500,000 16,800,000  
Current Risk Management Liabilities 14,900,000 2,000,000.0  
Derivative Liability, Noncurrent 1,700,000 0  
Total Liabilities 16,600,000 2,000,000.0  
Total MTM Derivative Contract Net Assets (Liabilities) (4,100,000) 14,800,000  
Gross Amounts Offset in the Statement of Financial Position [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets (394,300,000) (830,600,000)  
Derivative Asset, Noncurrent (234,400,000) (444,700,000)  
Current Risk Management Liabilities (417,100,000) (620,400,000)  
Derivative Liability, Noncurrent (194,900,000) (175,300,000)  
Gross Amounts Offset in the Statement of Financial Position [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities (200,000) 0  
Derivative Liability, Noncurrent 0 0  
Gross Amounts Offset in the Statement of Financial Position [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets (2,200,000) (200,000)  
Derivative Asset, Noncurrent (300,000) (700,000)  
Current Risk Management Liabilities (2,600,000) (500,000)  
Derivative Liability, Noncurrent (300,000) (600,000)  
Gross Amounts Offset in the Statement of Financial Position [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets (2,300,000) (800,000)  
Derivative Asset, Noncurrent (200,000) (300,000)  
Current Risk Management Liabilities (3,400,000) (900,000)  
Derivative Liability, Noncurrent (200,000) (300,000)  
Gross Amounts Offset in the Statement of Financial Position [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities (100,000) (300,000)  
Derivative Liability, Noncurrent 0 0  
Gross Amounts Offset in the Statement of Financial Position [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets (700,000) (400,000)  
Derivative Asset, Noncurrent 0 0  
Current Risk Management Liabilities (800,000) (500,000)  
Derivative Liability, Noncurrent 0 0  
Gross Amounts Offset in the Statement of Financial Position [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets (400,000) (400,000)  
Derivative Asset, Noncurrent (500,000) 0  
Current Risk Management Liabilities (500,000) (600,000)  
Derivative Liability, Noncurrent (500,000) 0  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 217,500,000 348,800,000  
Derivative Asset, Noncurrent 321,200,000 284,100,000  
Total Assets 538,700,000 632,900,000  
Current Risk Management Liabilities 229,600,000 145,200,000  
Derivative Liability, Noncurrent 241,800,000 345,200,000  
Total Liabilities 471,400,000 490,400,000  
Total MTM Derivative Contract Net Assets (Liabilities) 67,300,000 142,500,000  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | AEP Texas Inc. [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Total Assets 0 0  
Current Risk Management Liabilities 2,700,000 0  
Derivative Liability, Noncurrent 0 0  
Total Liabilities 2,700,000 0  
Total MTM Derivative Contract Net Assets (Liabilities) (2,700,000) 0  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Appalachian Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 22,400,000 69,100,000  
Derivative Asset, Noncurrent 0 0  
Total Assets 22,400,000 69,100,000  
Current Risk Management Liabilities 15,900,000 3,600,000  
Derivative Liability, Noncurrent 6,600,000 100,000  
Total Liabilities 22,500,000 3,700,000  
Total MTM Derivative Contract Net Assets (Liabilities) (100,000) 65,400,000  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Indiana Michigan Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 27,800,000 15,200,000  
Derivative Asset, Noncurrent 11,800,000 200,000  
Total Assets 39,600,000 15,400,000  
Current Risk Management Liabilities 2,000,000.0 0  
Derivative Liability, Noncurrent 0 0  
Total Liabilities 2,000,000.0 0  
Total MTM Derivative Contract Net Assets (Liabilities) 37,600,000 15,400,000  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Ohio Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 0 0  
Derivative Asset, Noncurrent 0 0  
Total Assets 0 0  
Current Risk Management Liabilities 6,800,000 1,800,000  
Derivative Liability, Noncurrent 43,900,000 37,900,000  
Total Liabilities 50,700,000 39,700,000  
Total MTM Derivative Contract Net Assets (Liabilities) (50,700,000) (39,700,000)  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Public Service Co Of Oklahoma [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 19,000,000.0 25,300,000  
Derivative Asset, Noncurrent 0 0  
Total Assets 19,000,000.0 25,300,000  
Current Risk Management Liabilities 28,900,000 1,600,000  
Derivative Liability, Noncurrent 1,000,000.0 0  
Total Liabilities 29,900,000 1,600,000  
Total MTM Derivative Contract Net Assets (Liabilities) (10,900,000) 23,700,000  
Net Amounts of Assets/Liabilities Presented in the Statement of Financial Position [Member] | Southwestern Electric Power Co [Member]      
Fair Value of Derivative Instruments      
Current Risk Management Assets 11,600,000 16,400,000  
Derivative Asset, Noncurrent 0 0  
Total Assets 11,600,000 16,400,000  
Current Risk Management Liabilities 14,400,000 1,400,000  
Derivative Liability, Noncurrent 1,200,000 0  
Total Liabilities 15,600,000 1,400,000  
Total MTM Derivative Contract Net Assets (Liabilities) $ (4,000,000.0) $ 15,000,000.0  
Power [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 246.8 226.8  
Power [Member] | AEP Texas Inc. [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 0.0 0.0  
Power [Member] | Appalachian Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 16.8 17.9  
Power [Member] | Indiana Michigan Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 5.9 4.2  
Power [Member] | Ohio Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 2.2 2.5  
Power [Member] | Public Service Co Of Oklahoma [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 4.1 2.9  
Power [Member] | Southwestern Electric Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MWh 2.9 2.2  
Natural Gas [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 151.6 77.1  
Natural Gas [Member] | AEP Texas Inc. [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 0.0 0.0  
Natural Gas [Member] | Appalachian Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 37.3 1.9  
Natural Gas [Member] | Indiana Michigan Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 0.0 0.0  
Natural Gas [Member] | Ohio Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 0.0 0.0  
Natural Gas [Member] | Public Service Co Of Oklahoma [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 34.9 1.9  
Natural Gas [Member] | Southwestern Electric Power Co [Member]      
Commodity      
Derivative, Energy Notional Amount | MMBTU 17.9 2.1  
Heating Oil and Gasoline [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 6.5 6.9  
Heating Oil and Gasoline [Member] | AEP Texas Inc. [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 1.8 1.9  
Heating Oil and Gasoline [Member] | Appalachian Power Co [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 1.0 1.0  
Heating Oil and Gasoline [Member] | Indiana Michigan Power Co [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 0.6 0.7  
Heating Oil and Gasoline [Member] | Ohio Power Co [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 1.2 1.4  
Heating Oil and Gasoline [Member] | Public Service Co Of Oklahoma [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 0.7 0.9  
Heating Oil and Gasoline [Member] | Southwestern Electric Power Co [Member]      
Commodity      
Derivative, Volume Notional Amount | gal 0.9 1.0  
Interest Rate Contract [Member]      
Commodity      
Derivative, Notional Amount $ 80,100,000 $ 99,900,000  
Interest Rate Contract [Member] | AEP Texas Inc. [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate Contract [Member] | Appalachian Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate Contract [Member] | Indiana Michigan Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate Contract [Member] | Ohio Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate Contract [Member] | Public Service Co Of Oklahoma [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Interest Rate Contract [Member] | Southwestern Electric Power Co [Member]      
Commodity      
Derivative, Notional Amount 0 0  
Vertically Integrated Utilities Revenues [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 24,600,000 11,100,000 (600,000)
Vertically Integrated Utilities Revenues [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Vertically Integrated Utilities Revenues [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Vertically Integrated Utilities Revenues [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Vertically Integrated Utilities Revenues [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Vertically Integrated Utilities Revenues [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Vertically Integrated Utilities Revenues [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (423,800,000) 313,800,000 169,100,000
Generation and Marketing Revenues [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Generation and Marketing Revenues [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Electric Generation, Transmission and Distribution Revenues [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Electric Generation, Transmission and Distribution Revenues [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Electric Generation, Transmission and Distribution Revenues [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 100,000 500,000 (500,000)
Electric Generation, Transmission and Distribution Revenues [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 24,500,000 10,600,000 (100,000)
Electric Generation, Transmission and Distribution Revenues [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Electric Generation, Transmission and Distribution Revenues [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Electric Generation, Transmission and Distribution Revenues [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member)      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 2,500,000 5,000,000.0 2,000,000.0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 2,300,000 4,500,000 1,800,000
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 100,000 100,000 0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 200,000 0
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (Member) | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 0 0
Other Operation Expense [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (200,000) 4,800,000 2,800,000
Other Operation Expense [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (100,000) 1,500,000 800,000
Other Operation Expense [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 400,000 300,000
Other Operation Expense [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 500,000 300,000
Other Operation Expense [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 800,000 500,000
Other Operation Expense [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 600,000 300,000
Other Operation Expense [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts 0 800,000 400,000
Maintenance Expense [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (800,000) 6,700,000 3,400,000
Maintenance Expense [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (300,000) 1,800,000 1,000,000.0
Maintenance Expense [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (100,000) 900,000 500,000
Maintenance Expense [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (100,000) 600,000 300,000
Maintenance Expense [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (100,000) 1,200,000 600,000
Maintenance Expense [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (100,000) 800,000 400,000
Maintenance Expense [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts (200,000) 1,100,000 500,000
Regulatory Assets [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (94,800,000) 52,600,000 (9,100,000)
Regulatory Assets [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (200,000) 100,000 0
Regulatory Assets [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (21,900,000) (100,000) (2,700,000)
Regulatory Assets [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (3,100,000) (800,000) (14,800,000)
Regulatory Assets [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (14,000,000.0) 52,100,000 10,000,000.0
Regulatory Assets [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (29,800,000) 3,600,000 (3,600,000)
Regulatory Assets [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] (15,500,000) (2,100,000) 3,600,000
Regulatory Liabilities [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 169,700,000 299,700,000 156,400,000
Regulatory Liabilities [Member] | AEP Texas Inc. [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 0 (600,000) 200,000
Regulatory Liabilities [Member] | Appalachian Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 1,000,000.0 82,400,000 55,900,000
Regulatory Liabilities [Member] | Indiana Michigan Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 7,800,000 8,600,000 (3,900,000)
Regulatory Liabilities [Member] | Ohio Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 0 3,700,000 0
Regulatory Liabilities [Member] | Public Service Co Of Oklahoma [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] 88,700,000 98,500,000 48,900,000
Regulatory Liabilities [Member] | Southwestern Electric Power Co [Member]      
Amount of Gain (Loss) Recognized on Risk Management Contracts      
Amount of Gain (Loss) Recognized on Risk Management Contracts [7] $ 70,700,000 $ 77,900,000 $ 37,000,000.0
[1] Amounts include $(30) million and $(38) million as of December 31, 2023 and 2022, respectively, for the fair value hedge adjustment of hedged debt obligations for which hedge accounting has been discontinued.
[2] Amounts included within Noncurrent Liabilities line item Long-term Debt on the Balance Sheet.
[3] Gain (Loss) is included in Interest Expense on the statements of income.
[4] The December 31, 2023 maturities of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), were as follows: Level 1 matures $(11) million in 2024 and $(4) million in 2025-2027; Level 2 matures $(99) million in 2024, $(44) million in periods 2025-2027, $7 million in periods 2028-2029 and $2 million in periods 2030-2033; Level 3 matures $74 million in 2024, $43 million in periods 2025-2027, $18 million in periods 2028-2029 and $(16) million in periods 2030-2033. Risk management commodity contracts are substantially comprised of power contracts.
[5] Amounts in “Other” column primarily represent counterparty netting of risk management and hedging contracts and associated cash collateral under the accounting guidance for “Derivatives and Hedging.”
[6] The December 31, 2022 maturities of the net fair value of risk management contracts prior to cash collateral, assets/(liabilities), were as follows:  Level 1 matures $(7) million in 2023; Level 2 matures $182 million in 2023, $134 million in periods 2024-2026; $10 million in periods 2027-2028 and $1 million in periods 2029-2033; Level 3 matures $128 million in 2023, $6 million in periods 2024-2026, $6 million in periods 2027-2028 and $(5) million in periods 2029-2033.  Risk management commodity contracts are substantially comprised of power contracts.
[7] Represents realized and unrealized gains and losses subject to regulatory accounting treatment recorded as either current or noncurrent on the balance sheets.