v3.24.0.1
Property, Plant and Equipment (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 24,329.5 $ 25,834.2  
Property, Plant and Equipment, Transmission 35,934.1 33,266.9  
Property, Plant and Equipment, Distribution 28,989.9 27,138.8  
Property, Plant and Equipment, Other 6,484.9 5,971.8  
Property, Plant and Equipment, Construction Work in Progress 5,508.0 4,809.7  
Accumulated Depreciation 24,553.0 23,682.3  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 76,693.4 73,339.1  
Asset Retirement Obligations (ARO)      
Beginning Balance [1],[2],[3],[4],[5],[6] 2,943.6 2,741.7  
Accretion Expense [1],[2],[3],[4],[5],[6] 116.3 111.2  
Liabilities Incurred [1],[2],[3],[4],[5],[6] 38.9 37.4  
Liabilities Settled [1],[2],[3],[4],[5],[6] (130.6) (47.0)  
Revisions in Cash Flow Estimates [1],[2],[3],[4],[5],[6],[7] 63.0 100.3  
Ending Balance [1],[2],[3],[4],[5],[6] 3,031.2 2,943.6 $ 2,741.7
Asset Retirement Obligations (ARO) Liability for Nuclear Decommissioning of the Cook Plant 2,110.0 2,000.0  
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 174.9 133.7 139.7
Allowance for Borrowed Funds Used During Construction 117.3 63.0 53.8
Jointly-owned Electric Facilities      
Utility Plant in Service 1,906.8 2,626.0  
Construction Work in Progress 11.7 21.5  
Accumulated Depreciation 490.8 1,096.1  
Asset Impairments and Other Related Charges 85.6 48.8 11.6
Competitive Contracted Renewable Portfolio      
Asset Retirement Obligations (ARO)      
Liabilities Settled (31.0)    
AEP Texas Inc. [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Transmission 6,812.6 6,301.5  
Property, Plant and Equipment, Distribution 5,798.8 5,312.8  
Property, Plant and Equipment, Other 1,145.9 1,022.8  
Property, Plant and Equipment, Construction Work in Progress 904.6 805.2  
Accumulated Depreciation 1,887.9 1,760.7  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 12,774.0 11,681.6  
Asset Retirement Obligations (ARO)      
Beginning Balance [3],[4] 4.5 4.4  
Accretion Expense [3],[4] 0.2 0.3  
Liabilities Incurred [3],[4] 0.0 0.0  
Liabilities Settled [3],[4] (0.3) (0.2)  
Revisions in Cash Flow Estimates [3],[4],[7] 0.1 0.0  
Ending Balance [3],[4] 4.5 4.5 4.4
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 28.4 19.7 21.5
Allowance for Borrowed Funds Used During Construction 23.4 11.5 10.5
AEP Transmission Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Transmission 13,723.9 12,335.4  
Property, Plant and Equipment, Other 501.4 476.8  
Property, Plant and Equipment, Construction Work in Progress 1,563.7 1,554.7  
Accumulated Depreciation 1,291.3 1,027.0  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 14,497.7 13,339.9  
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 83.2 70.7 67.2
Allowance for Borrowed Funds Used During Construction 31.4 22.4 21.0
Appalachian Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation 7,041.3 6,776.8  
Property, Plant and Equipment, Transmission 4,711.8 4,482.8  
Property, Plant and Equipment, Distribution 5,176.6 4,933.0  
Property, Plant and Equipment, Other 981.3 883.3  
Property, Plant and Equipment, Construction Work in Progress 709.2 705.3  
Accumulated Depreciation 5,688.7 5,402.0  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 12,931.5 12,379.2  
Asset Retirement Obligations (ARO)      
Beginning Balance [3],[4] 427.7 404.6  
Accretion Expense [3],[4] 16.8 15.8  
Liabilities Incurred [3],[4] 16.1 3.0  
Liabilities Settled [3],[4] (23.1) (12.7)  
Revisions in Cash Flow Estimates [3],[4],[7] 26.5 17.0  
Ending Balance [3],[4] 464.0 427.7 404.6
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 11.9 11.7 15.6
Allowance for Borrowed Funds Used During Construction 14.1 6.5 7.5
Jointly-owned Electric Facilities      
Asset Impairments and Other Related Charges 0.0 24.9 0.0
Indiana Michigan Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation 5,646.8 5,585.1  
Property, Plant and Equipment, Transmission 1,906.4 1,842.2  
Property, Plant and Equipment, Distribution 3,254.0 3,024.7  
Property, Plant and Equipment, Other 898.5 839.3  
Property, Plant and Equipment, Construction Work in Progress 301.7 253.0  
Accumulated Depreciation 4,378.4 4,132.8  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 7,629.0 7,411.5  
Asset Retirement Obligations (ARO)      
Beginning Balance [3],[4],[5] 2,028.1 1,946.3  
Accretion Expense [3],[4],[5] 74.8 71.5  
Liabilities Incurred [3],[4],[5] 4.8 3.2  
Liabilities Settled [3],[4],[5] (3.7) (0.6)  
Revisions in Cash Flow Estimates [3],[4],[5],[7] 2.0 7.7  
Ending Balance [3],[4],[5] 2,106.0 2,028.1 1,946.3
Asset Retirement Obligations (ARO) Liability for Nuclear Decommissioning of the Cook Plant 2,110.0 2,000.0  
Fair Value of Legally Restricted Assets 3,510.0 3,010.0  
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 10.9 9.8 12.8
Allowance for Borrowed Funds Used During Construction 7.7 5.7 5.1
Ohio Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Transmission 3,395.1 3,198.6  
Property, Plant and Equipment, Distribution 6,839.4 6,450.3  
Property, Plant and Equipment, Other 1,125.0 1,051.4  
Property, Plant and Equipment, Construction Work in Progress 654.0 474.3  
Accumulated Depreciation 2,713.6 2,565.3  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 9,299.9 8,609.3  
Asset Retirement Obligations (ARO)      
Beginning Balance [4] 5.0 1.9  
Accretion Expense [4] 0.2 0.2  
Liabilities Incurred [4] 0.0 3.0  
Liabilities Settled [4] (3.1) (0.1)  
Revisions in Cash Flow Estimates [4],[7] 0.0 0.0  
Ending Balance [4] 2.1 5.0 1.9
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 17.1 13.9 10.8
Allowance for Borrowed Funds Used During Construction 14.0 6.7 4.7
Public Service Co Of Oklahoma [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation 2,695.5 2,394.8  
Property, Plant and Equipment, Transmission 1,228.3 1,164.4  
Property, Plant and Equipment, Distribution 3,450.8 3,216.4  
Property, Plant and Equipment, Other 505.9 469.3  
Property, Plant and Equipment, Construction Work in Progress 313.7 219.3  
Accumulated Depreciation 2,081.9 1,837.7  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 6,112.3 5,626.5  
Asset Retirement Obligations (ARO)      
Beginning Balance [1],[3],[4] 75.7 57.6  
Accretion Expense [1],[3],[4] 4.7 4.1  
Liabilities Incurred [1],[3],[4] 5.8 12.8  
Liabilities Settled [1],[3],[4] (1.2) (0.7)  
Revisions in Cash Flow Estimates [1],[3],[4],[7] (0.8) 1.9  
Ending Balance [1],[3],[4] 84.2 75.7 57.6
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 8.4 1.5 2.4
Allowance for Borrowed Funds Used During Construction 5.2 2.7 0.7
Southwestern Electric Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation 4,790.7 5,476.2  
Property, Plant and Equipment, Transmission 2,660.6 2,479.8  
Property, Plant and Equipment, Distribution 2,824.1 2,659.6  
Property, Plant and Equipment, Other 814.4 804.4  
Property, Plant and Equipment, Construction Work in Progress 555.8 369.5  
Accumulated Depreciation 3,087.2 3,527.3  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 8,558.4 8,262.2  
Asset Retirement Obligations (ARO)      
Beginning Balance [1],[2],[3],[4] 280.9 222.7  
Accretion Expense [1],[2],[3],[4] 13.7 11.9  
Liabilities Incurred [1],[2],[3],[4] 7.5 15.4  
Liabilities Settled [1],[2],[3],[4] (55.0) (25.8)  
Revisions in Cash Flow Estimates [1],[2],[3],[4],[7] 34.5 56.7  
Ending Balance [1],[2],[3],[4] 281.6 280.9 222.7
Allowance for Funds Used During Construction (AFUDC) and Interest Capitalization      
Allowance for Equity Funds Used During Construction 11.5 4.9 7.0
Allowance for Borrowed Funds Used During Construction 9.8 4.3 3.0
Jointly-owned Electric Facilities      
Utility Plant in Service 2,993.1 3,692.8  
Construction Work in Progress 14.6 31.6  
Accumulated Depreciation 558.7 1,131.3  
Asset Impairments and Other Related Charges $ 85.6 $ 0.0 $ 11.6
Flint Creek Generating Station (Unit No. 1) [Member] | Coal [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 50.00% 50.00%  
Utility Plant in Service [8] $ 402.8 $ 382.9  
Construction Work in Progress [8] 1.6 16.4  
Accumulated Depreciation [8] $ 167.5 $ 149.4  
Flint Creek Generating Station (Unit No. 1) [Member] | Southwestern Electric Power Co [Member] | Coal [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 50.00% 50.00%  
Utility Plant in Service [8] $ 402.8 $ 382.9  
Construction Work in Progress [8] 1.6 16.4  
Accumulated Depreciation [8] $ 167.5 $ 149.4  
Pirkey Generating Station (Unit No. 1) [Member] | Public Utilities, Inventory, Lignite [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 85.90% [9] 85.90%  
Utility Plant in Service [8] $ 0.0 [9] $ 632.0  
Construction Work in Progress [8] 0.0 [9] 0.0  
Accumulated Depreciation [8] $ 0.0 [9] $ 632.0  
Pirkey Generating Station (Unit No. 1) [Member] | Southwestern Electric Power Co [Member] | Public Utilities, Inventory, Lignite [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 85.90% [9] 85.90%  
Utility Plant in Service [8] $ 0.0 [9] $ 632.0  
Construction Work in Progress [8] 0.0 [9] 0.0  
Accumulated Depreciation [8] $ 0.0 [9] $ 632.0  
Turk Generating Plant [Member] | Coal [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 73.30% [10] 73.30%  
Utility Plant in Service [8] $ 1,504.0 [10] $ 1,611.1  
Construction Work in Progress [8] 10.1 [10] 5.1  
Accumulated Depreciation [8] $ 323.3 [10] $ 314.7  
Turk Generating Plant [Member] | Southwestern Electric Power Co [Member] | Coal [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [8] 73.30% [10] 73.30%  
Utility Plant in Service [8] $ 1,504.0 [10] $ 1,611.1  
Construction Work in Progress [8] 10.1 [10] 5.1  
Accumulated Depreciation [8] $ 323.3 [10] $ 314.7  
NCWF [Member] | Public Service Co Of Oklahoma [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership 45.50%    
NCWF [Member] | Public Service Co Of Oklahoma [Member] | Wind [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [11],[12] 45.50% 45.50%  
Utility Plant in Service [11],[12] $ 906.3 $ 889.3  
Construction Work in Progress [11],[12] 2.4 9.1  
Accumulated Depreciation [11],[12] $ 54.1 $ 28.1  
NCWF [Member] | Southwestern Electric Power Co [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership 54.50%    
NCWF [Member] | Southwestern Electric Power Co [Member] | Wind [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [11],[12] 54.50% 54.50%  
Utility Plant in Service [11],[12] $ 1,086.3 $ 1,066.8  
Construction Work in Progress [11],[12] 2.9 10.1  
Accumulated Depreciation [11],[12] $ 67.9 $ 35.2  
Rockport Generating Plant | Indiana Michigan Power Co [Member] | Coal [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership [13],[14] 50.00% 50.00%  
Utility Plant in Service [13],[14] $ 1,341.4 $ 1,357.4  
Construction Work in Progress [13],[14] 7.9 9.2  
Accumulated Depreciation [13],[14] $ 1,018.9 905.1  
Rockport Generating Plant | AEP Generating Co [Member]      
Jointly-owned Electric Facilities      
Percent of Ownership 50.00%    
Regulated Operation [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation [15] $ 23,862.7 23,759.7  
Property, Plant and Equipment, Transmission 35,903.6 33,221.7  
Property, Plant and Equipment, Distribution 28,989.9 27,138.8  
Property, Plant and Equipment, Other 5,986.1 5,528.9  
Property, Plant and Equipment, Construction Work in Progress [15] 5,480.6 4,776.4  
Accumulated Depreciation 24,093.8 23,118.0  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 76,129.1 $ 71,307.5  
Regulated Operation [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 162 years 132 years 132 years
Depreciable Life Ranges - Transmission 78 years 75 years 75 years
Depreciable Life Ranges - Distribution 85 years 78 years 80 years
Depreciable Life Ranges - Other 75 years 75 years 75 years
Regulated Operation [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 20 years 20 years 20 years
Depreciable Life Ranges - Transmission 15 years 24 years 15 years
Depreciable Life Ranges - Distribution 7 years 7 years 7 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Generation [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 4.70% 7.60% 7.80%
Regulated Operation [Member] | Generation [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.70% 2.70% 2.70%
Regulated Operation [Member] | Transmission [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.70% 2.70% 2.60%
Regulated Operation [Member] | Transmission [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.00% 2.00% 2.00%
Regulated Operation [Member] | Distribution [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.60% 3.60% 3.60%
Regulated Operation [Member] | Distribution [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 2.70% 2.80%
Regulated Operation [Member] | Other Property Class [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 9.10% 14.40% 12.50%
Regulated Operation [Member] | Other Property Class [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.80% 3.10% 3.00%
Regulated Operation [Member] | AEP Texas Inc. [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 0.0 $ 0.0  
Property, Plant and Equipment, Transmission 6,812.6 6,301.5  
Property, Plant and Equipment, Distribution 5,798.8 5,312.8  
Property, Plant and Equipment, Other 1,142.9 1,020.4  
Property, Plant and Equipment, Construction Work in Progress 904.6 805.2  
Accumulated Depreciation 1,886.7 1,759.5  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 12,772.2 $ 11,680.4  
Regulated Operation [Member] | AEP Texas Inc. [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 75 years 75 years 75 years
Depreciable Life Ranges - Distribution 70 years 70 years 70 years
Depreciable Life Ranges - Other 50 years 50 years 50 years
Regulated Operation [Member] | AEP Texas Inc. [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 50 years 50 years 50 years
Depreciable Life Ranges - Distribution 7 years 7 years 7 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | AEP Texas Inc. [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.20% 2.20% 2.20%
Regulated Operation [Member] | AEP Texas Inc. [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 2.90% 2.90%
Regulated Operation [Member] | AEP Texas Inc. [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 6.00% 6.20% 5.80%
Regulated Operation [Member] | AEP Transmission Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 0.0 $ 0.0  
Property, Plant and Equipment, Transmission 13,723.9 12,335.4  
Property, Plant and Equipment, Distribution 0.0 0.0  
Property, Plant and Equipment, Other 501.2 476.6  
Property, Plant and Equipment, Construction Work in Progress 1,563.7 1,554.7  
Accumulated Depreciation 1,291.4 1,027.1  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 14,497.4 $ 13,339.6  
Regulated Operation [Member] | AEP Transmission Co [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 78 years 75 years 75 years
Depreciable Life Ranges - Other 58 years 56 years 56 years
Regulated Operation [Member] | AEP Transmission Co [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 24 years 24 years 24 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | AEP Transmission Co [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.60% 2.60% 2.50%
Regulated Operation [Member] | AEP Transmission Co [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 7.00% 6.60% 6.70%
Regulated Operation [Member] | Appalachian Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 7,041.3 $ 6,776.8  
Property, Plant and Equipment, Transmission 4,711.8 4,482.8  
Property, Plant and Equipment, Distribution 5,176.6 4,933.0  
Property, Plant and Equipment, Other 943.7 849.2  
Property, Plant and Equipment, Construction Work in Progress 709.2 705.3  
Accumulated Depreciation 5,684.0 5,397.3  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 12,898.6 $ 12,349.8  
Regulated Operation [Member] | Appalachian Power Co [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 162 years 118 years 118 years
Depreciable Life Ranges - Transmission 78 years 75 years 75 years
Depreciable Life Ranges - Distribution 60 years 57 years 57 years
Depreciable Life Ranges - Other 55 years 55 years 55 years
Regulated Operation [Member] | Appalachian Power Co [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 35 years 35 years 35 years
Depreciable Life Ranges - Transmission 15 years 24 years 15 years
Depreciable Life Ranges - Distribution 12 years 12 years 12 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Appalachian Power Co [Member] | Generation [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.30% 3.60% 3.60%
Regulated Operation [Member] | Appalachian Power Co [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.30% 2.20% 2.10%
Regulated Operation [Member] | Appalachian Power Co [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.60% 3.60% 3.50%
Regulated Operation [Member] | Appalachian Power Co [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 7.40% 7.30% 8.50%
Regulated Operation [Member] | Indiana Michigan Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 5,588.7 $ 5,534.6  
Property, Plant and Equipment, Transmission 1,906.4 1,842.2  
Property, Plant and Equipment, Distribution 3,254.0 3,024.7  
Property, Plant and Equipment, Other 856.8 796.1  
Property, Plant and Equipment, Construction Work in Progress 294.1 253.0  
Accumulated Depreciation 4,353.7 4,117.8  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 7,546.3 $ 7,332.8  
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 132 years 132 years 132 years
Depreciable Life Ranges - Transmission 67 years 67 years 70 years
Depreciable Life Ranges - Distribution 71 years 71 years 71 years
Depreciable Life Ranges - Other 45 years 45 years 51 years
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 20 years 20 years 20 years
Depreciable Life Ranges - Transmission 44 years 44 years 45 years
Depreciable Life Ranges - Distribution 14 years 14 years 14 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Generation [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 4.70% 4.90% 4.70%
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.50% 2.50% 2.40%
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 3.10% 3.40%
Regulated Operation [Member] | Indiana Michigan Power Co [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 9.10% 10.10% 9.00%
Regulated Operation [Member] | Ohio Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 0.0 $ 0.0  
Property, Plant and Equipment, Transmission 3,395.1 3,198.6  
Property, Plant and Equipment, Distribution 6,839.4 6,450.3  
Property, Plant and Equipment, Other 1,114.4 1,040.6  
Property, Plant and Equipment, Construction Work in Progress 654.0 474.3  
Accumulated Depreciation 2,712.7 2,564.3  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 9,290.2 $ 8,599.5  
Regulated Operation [Member] | Ohio Power Co [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 60 years 60 years 60 years
Depreciable Life Ranges - Distribution 70 years 70 years 70 years
Depreciable Life Ranges - Other 50 years 50 years 50 years
Regulated Operation [Member] | Ohio Power Co [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Transmission 39 years 39 years 39 years
Depreciable Life Ranges - Distribution 11 years 11 years 11 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Ohio Power Co [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.30% 2.30% 2.30%
Regulated Operation [Member] | Ohio Power Co [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.10% 2.70% 2.90%
Regulated Operation [Member] | Ohio Power Co [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 6.40% 6.10% 6.10%
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation $ 2,695.5 $ 2,394.8  
Property, Plant and Equipment, Transmission 1,228.3 1,164.4  
Property, Plant and Equipment, Distribution 3,450.8 3,216.4  
Property, Plant and Equipment, Other 502.7 466.0  
Property, Plant and Equipment, Construction Work in Progress 313.7 219.3  
Accumulated Depreciation 2,083.6 1,839.4  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 6,107.4 $ 5,621.5  
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 75 years 75 years 75 years
Depreciable Life Ranges - Transmission 75 years 75 years 75 years
Depreciable Life Ranges - Distribution 85 years 78 years 78 years
Depreciable Life Ranges - Other 58 years 56 years 56 years
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 25 years 30 years 30 years
Depreciable Life Ranges - Transmission 41 years 42 years 42 years
Depreciable Life Ranges - Distribution 15 years 15 years 15 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Generation [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 3.00% 3.10% 2.80%
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.60% 2.50% 2.40%
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 2.90% 2.90%
Regulated Operation [Member] | Public Service Co Of Oklahoma [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 6.80% 6.80% 6.10%
Regulated Operation [Member] | Southwestern Electric Power Co [Member]      
Depreciation, Depletion and Amortization      
Property, Plant and Equipment, Generation [15] $ 4,790.7 $ 5,476.2  
Property, Plant and Equipment, Transmission 2,660.6 2,479.8  
Property, Plant and Equipment, Distribution 2,824.1 2,659.6  
Property, Plant and Equipment, Other 544.1 582.6  
Property, Plant and Equipment, Construction Work in Progress [15] 555.8 369.5  
Accumulated Depreciation 2,840.8 3,314.8  
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 8,534.5 $ 8,252.9  
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 65 years 65 years 65 years
Depreciable Life Ranges - Transmission 70 years 70 years 74 years
Depreciable Life Ranges - Distribution 75 years 75 years 80 years
Depreciable Life Ranges - Other 58 years 57 years 58 years
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 30 years 30 years 30 years
Depreciable Life Ranges - Transmission 46 years 44 years 49 years
Depreciable Life Ranges - Distribution 7 years 15 years 15 years
Depreciable Life Ranges - Other 5 years 5 years 5 years
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Generation [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 2.70% 2.70%
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.20% 2.30% 2.40%
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Distribution [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.90% 2.90% 2.80%
Regulated Operation [Member] | Southwestern Electric Power Co [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 8.50% 9.00% 8.60%
Unregulated Operation [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 564.3 $ 2,031.6  
Unregulated Operation [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 61 years 61 years 59 years
Depreciable Life Ranges - Transmission   62 years 40 years
Depreciable Life Ranges - Other [16] 35 years 35 years 35 years
Unregulated Operation [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Depreciable Life Ranges - Generation 10 years 3 years 10 years
Depreciable Life Ranges - Transmission 62 years 10 years 30 years
Depreciable Life Ranges - Other [16] 5 years 5 years 5 years
Unregulated Operation [Member] | Generation [Member] | Maximum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 6.70% 8.70% 10.40%
Unregulated Operation [Member] | Generation [Member] | Minimum [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 4.80% 3.80% 3.80%
Unregulated Operation [Member] | Transmission [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 2.50% 2.80% 2.60%
Unregulated Operation [Member] | Other Property Class [Member]      
Depreciation, Depletion and Amortization      
Annual Composite Depreciation Rate 10.60% 25.20% 16.50%
Unregulated Operation [Member] | AEP Texas Inc. [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET $ 1.8 $ 1.2  
Unregulated Operation [Member] | AEP Transmission Co [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 0.3 0.3  
Unregulated Operation [Member] | Appalachian Power Co [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 32.9 29.4  
Unregulated Operation [Member] | Indiana Michigan Power Co [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 82.7 78.7  
Unregulated Operation [Member] | Ohio Power Co [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 9.7 9.8  
Unregulated Operation [Member] | Public Service Co Of Oklahoma [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 4.9 5.0  
Unregulated Operation [Member] | Southwestern Electric Power Co [Member]      
Depreciation, Depletion and Amortization      
TOTAL PROPERTY, PLANT AND EQUIPMENT - NET 23.9 9.3  
Cook Nuclear Plant [Member] | Indiana Michigan Power Co [Member]      
Asset Retirement Obligations (ARO)      
Asset Retirement Obligations (ARO) Liability for Nuclear Decommissioning of the Cook Plant 2,110.0 2,000.0  
Amos Plant | Appalachian Power Co [Member]      
Asset Retirement Obligations (ARO)      
Revisions in Cash Flow Estimates   14.0  
Traverse [Member] | Public Service Co Of Oklahoma [Member]      
Asset Retirement Obligations (ARO)      
Liabilities Incurred   13.0  
Traverse [Member] | Southwestern Electric Power Co [Member]      
Asset Retirement Obligations (ARO)      
Liabilities Incurred   15.0  
Pirkey Power Plant | Southwestern Electric Power Co [Member]      
Asset Retirement Obligations (ARO)      
Revisions in Cash Flow Estimates   13.0  
Sabine Mining Co [Member] | Southwestern Electric Power Co [Member]      
Property, Plant and Equipment (Textuals)      
Asset Retirement Obligation, Revision of Estimate, Estimated Reclamation Costs - 1 32.0 16.0  
Asset Retirement Obligation, Revision of Estimate, Estimated Reclamation Costs - 2   7.0  
Pirkey Power Plant | Southwestern Electric Power Co [Member]      
Asset Retirement Obligations (ARO)      
Revisions in Cash Flow Estimates   14.0  
Pirkey Power Plant and Dolet Hills Power Station | Southwestern Electric Power Co [Member]      
Asset Retirement Obligations (ARO)      
Liabilities Settled (50.0)    
Various Plants | Appalachian Power Co [Member]      
Asset Retirement Obligations (ARO)      
Revisions in Cash Flow Estimates 27.0    
Generation and Marketing [Member]      
Jointly-owned Electric Facilities      
Asset Impairments and Other Related Charges $ 0.0 $ 0.0 $ 0.0
[1] Includes ARO related to wind farms.
[2] Includes ARO related to Sabine and DHLC.
[3] Includes ARO related to ash disposal facilities.
[4] Includes ARO related to asbestos removal.
[5] Includes ARO related to nuclear decommissioning costs for the Cook Plant of $2.11 billion and $2 billion as of December 31, 2023 and 2022, respectively.
[6] Includes ARO related to solar farms.
[7] Unless discussed above, primarily related to ash ponds, landfills and mine reclamation, generally due to changes in estimated closure area, volumes and/or unit costs.
[8] Operated by SWEPCo.
[9] Pirkey Plant was retired in March 2023. See "Coal-Fired Generation Plants" of Note 5 for additional information.
[10] Includes impact of regulatory disallowance of AFUDC. See “2012 Texas Base Rate Case” section of Note 4 for additional information.
[11] Operated by PSO.
[12] PSO and SWEPCo own undivided interests of 45.5% and 54.5% of the NCWF, respectively.
[13] Operated by I&M.
[14] AEGCo owns 50%.
[15] AEP and SWEPCo’s regulated generation and regulated CWIP include amounts related to SWEPCo’s Arkansas jurisdictional share of the Turk Plant.
[16] In 2020, management announced plans to retire the Pirkey Plant in 2023 and the related depreciable lives have been adjusted accordingly. Pirkey Plant was retired in March 2023. See "Coal-Fired Generation Plants" of Note 5 for additional information.