XML 89 R60.htm IDEA: XBRL DOCUMENT
v3.23.1

Effects of Regulation (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | $ 73,339.1 | $ 68,304.1 |
Materials and Supplies |  | 915.1 | 701.8 |
Annual Depreciation |  | 3,072.8 | 2,717.1 | $ 2,487.5
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 1,310.0 | 656.0 |
Noncurrent Regulatory Assets |  | 4,762.0 | 4,618.8 |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | 1.4 | 1.5 |
Noncurrent Regulatory Liabilities |  | 8,115.6 | 8,834.4 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [1],[2],[3],[4],[5],[6],[7] | 100.3 | 138.6 |
Secured Debt |  | 487.8 | 603.5 |
Accumulated Depreciation and Amortization |  | 23,682.3 | 21,920.9 |
Asset Impairments and Other Related Charges |  | 48.8 | 11.6 | 0.0
AEP Texas Inc. [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 11,681.6 | 10,635.4 |
Materials and Supplies |  | 138.8 | 73.9 |
Annual Depreciation |  | 363.5 | 327.2 | 364.2
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 298.3 | 275.2 |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,259.6 | 1,242.0 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [2],[3],[7] | 0.0 | 0.0 |
Secured Debt |  | 314.4 | 404.7 |
Accumulated Depreciation and Amortization |  | 1,760.7 | 1,644.1 |
AEP Transmission Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 13,339.9 | 12,101.0 |
Materials and Supplies |  | 10.7 | 9.3 |
Annual Depreciation |  | 346.2 | 297.3 | 249.0
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 7.2 | 8.5 |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 723.3 | 651.7 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Accumulated Depreciation and Amortization |  | 1,027.0 | 784.1 |
Appalachian Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 12,379.2 | 11,804.3 |
Materials and Supplies |  | 130.6 | 109.8 |
Annual Depreciation |  | 576.1 | 547.0 | 507.8
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 473.1 | 201.3 |
Noncurrent Regulatory Assets |  | 1,058.6 | 757.6 |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,143.6 | 1,238.8 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [2],[3],[7] | 17.0 | 84.7 |
Secured Debt |  | 173.3 | 198.8 |
Accumulated Depreciation and Amortization |  | 5,402.0 | 5,051.8 |
Asset Impairments and Other Related Charges |  | 24.9 | 0.0 | 0.0
Indiana Michigan Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 7,411.5 | 7,310.9 |
Materials and Supplies |  | 188.1 | 175.2 |
Annual Depreciation |  | 511.9 | 424.9 | 393.3
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 47.1 | 6.4 |
Noncurrent Regulatory Assets |  | 459.6 | 410.9 |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | 0.0 | 1.5 |
Noncurrent Regulatory Liabilities |  | 1,702.2 | 2,447.9 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [2],[3],[4],[7] | 7.7 | 59.4 |
Accumulated Depreciation and Amortization |  | 4,132.8 | 3,899.8 |
Ohio Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 8,609.3 | 7,963.0 |
Materials and Supplies |  | 109.5 | 74.1 |
Annual Depreciation |  | 293.1 | 301.1 | 275.0
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 3.8 | 0.0 |
Noncurrent Regulatory Assets |  | 327.3 | 293.0 |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,044.0 | 1,020.9 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [2],[7] | 0.0 | 0.0 |
Accumulated Depreciation and Amortization |  | 2,565.3 | 2,458.3 |
Public Service Co Of Oklahoma [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 5,626.5 | 4,802.8 |
Materials and Supplies |  | 111.1 | 56.2 |
Annual Depreciation |  | 226.2 | 185.9 | 171.9
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 178.7 | 194.6 |
Noncurrent Regulatory Assets |  | 653.7 | 1,037.4 |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 809.1 | 835.3 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [2],[3],[6],[7] | 1.9 | 0.0 |
Accumulated Depreciation and Amortization |  | 1,837.7 | 1,705.2 |
Southwestern Electric Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 8,262.2 | 7,400.1 |
Materials and Supplies |  | 92.1 | 81.9 |
Annual Depreciation |  | 319.3 | 292.9 | 271.2
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | 353.0 | 143.9 |
Noncurrent Regulatory Assets |  | 1,042.4 | 1,005.3 |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | 1.4 | 0.0 |
Noncurrent Regulatory Liabilities |  | 825.7 | 806.9 |
Effects of Regulation Textuals [Abstract] |  |  |  |
Revisions in Cash Flow Estimates | [1],[2],[3],[6],[7] | 56.7 | 2.5 |
Accumulated Depreciation and Amortization |  | 3,527.3 | 3,170.3 |
Asset Impairments and Other Related Charges |  | 0.0 | 11.6 | $ 0.0
Net Under-Recovered Fuel Costs |  | 257.0 |  |
Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 7,961.8 | 8,569.9 |
Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,244.8 | 1,229.0 |
Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,113.1 | 1,234.3 |
Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,789.9 | 2,447.9 |
Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,043.8 | 1,020.7 |
Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 757.8 | 779.1 |
Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 818.7 | 806.9 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 153.8 | 264.5 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 14.8 | 13.0 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 8.7 | 8.7 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 30.5 | 4.5 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | (87.7) | 0.0 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 0.2 | 0.2 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 51.3 | 56.2 |
Regulatory Liabilities Pending Final Regulatory Determination [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 7.0 | 0.0 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 5,983.4 | 6,057.2 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,202.7 | 1,194.8 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 714.6 | 643.0 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,005.1 | 1,136.5 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 365.5 | 384.2 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 918.4 | 948.2 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 696.4 | 724.0 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 811.0 | 793.9 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 149.7 | 262.2 |
Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 13.0 | 13.0 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,978.4 | 2,512.7 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 42.1 | 34.2 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 108.0 | 97.8 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1,424.4 | 2,063.7 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 125.4 | 72.5 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 61.4 | 55.1 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 7.7 | 13.0 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 4.1 | 2.3 |
Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1.8 | 0.0 |
Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 882.1 | 1,090.9 |
Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 67.0 | 41.2 |
Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 144.5 | 105.1 |
Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 23.7 | 3.7 |
Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 33.8 | 3.8 |
Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 510.2 | 817.9 |
Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 3,879.9 | 3,527.9 |
Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 231.3 | 234.0 |
Regulatory Assets Approved for Recovery [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 7.2 | 8.5 |
Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 914.1 | 652.5 |
Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 435.9 | 407.2 |
Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 293.5 | 289.2 |
Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 628.1 | 1,023.2 |
Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 532.2 | 187.4 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 355.6 | 695.6 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 17.6 | 0.0 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 7.0 | 6.8 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.1 | 0.1 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 330.9 | 641.2 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 1,858.6 | 1,841.8 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 17.5 | 35.4 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 299.3 | 110.4 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 270.6 | 303.3 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 34.9 | 56.9 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 552.8 | 981.5 |
Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 321.8 | 29.9 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 526.5 | 395.3 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 49.4 | 41.2 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 137.5 | 98.3 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 23.6 | 3.6 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 25.6 | 14.2 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 179.3 | 176.7 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 2,021.3 | 1,686.1 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 213.8 | 198.6 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 614.8 | 542.1 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 165.3 | 103.9 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 258.6 | 232.3 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 75.3 | 41.7 |
Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 210.4 | 157.5 |
Northeastern Plant, Unit 3 [Member] | Generating Units Probable of Abandonment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 136.3 |  |
Accelerated Depreciation Regulatory Asset |  | 145.8 |  |
Cost of Removal Regulatory Liability | [8] | $ 20.2 |  |
Expected Retirement Date | [9] | 2026 |  |
Annual Depreciation | [10] | $ 14.9 |  |
Dolet Hills Power Station [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Recommended Dolet Hills Fuel Disallowance |  | 72.0 |  |
Pirkey Power Plant [Member] | Generating Units Probable of Abandonment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 35.1 |  |
Accelerated Depreciation Regulatory Asset |  | 179.5 |  |
Cost of Removal Regulatory Liability |  | $ 39.8 |  |
Expected Retirement Date | [11] | 2023 |  |
Annual Depreciation | [10] | $ 11.7 |  |
Welsh Plant, Units 1 and 3 [Member] | Generating Units Probable of Abandonment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulated Generating Unit to be Retired |  |  |  |
Net Investment |  | 416.8 |  |
Accelerated Depreciation Regulatory Asset |  | 85.6 |  |
Cost of Removal Regulatory Liability | [12] | $ 58.3 |  |
Expected Retirement Date | [13] | 2028 |  |
Annual Depreciation | [10] | $ 37.9 |  |
Deferred Fuel Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | $ 1.4 | 0.0 |
Remaining Refund Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities | [14] | $ 1.4 | 0.0 |
Deferred Fuel Costs [Member] | Regulatory Liabilities Currently Not Paying Return [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | 0.0 | 1.5 |
Deferred Fuel Costs [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Indiana Michigan Power Co [Member] | Indiana |  |  |  |
Regulatory Liabilities |  |  |  |
Current Regulatory Liabilities |  | 0.0 | 1.5 |
Deferred Fuel Costs [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 32.2 | 15.2 |
Remaining Refund Period |  | 10 years |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Earning Return [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 625.7 | 409.4 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 180.7 | 127.2 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Indiana Michigan Power Co [Member] | Michigan |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 9.0 | 6.4 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 178.7 | 194.6 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets | [15] | $ 257.2 | 81.2 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 588.5 | 183.9 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 292.4 | 74.1 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Indiana Michigan Power Co [Member] | Indiana |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 38.1 | 0.0 |
Remaining Recovery Period |  | 1 year |  |
Deferred Fuel Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets |  | $ 3.8 | 0.0 |
Remaining Recovery Period |  | 1 year |  |
Dolet Hills Power Station Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [16] | $ 9.7 | 72.3 |
Dolet Hills Power Station Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [17] | 9.7 | 72.3 |
Kentucky Deferred Purchase Power Expenses [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.0 | 47.5 |
Kentucky Deferred Purchase Power Expenses [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 53.0 | 0.0 |
Remaining Recovery Period |  | 5 years |  |
Plant Retirement Costs - Unrecovered Plant, Louisiana [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 0.0 | 35.2 |
Plant Retirement Costs - Unrecovered Plant, Louisiana [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.0 | 35.2 |
Pirkey Power Plant Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 116.5 | 87.0 |
Pirkey Power Plant Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 116.5 | 87.0 |
Pirkey Power Plant Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Louisiana Jurisdiction [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 63.0 | 0.0 |
Remaining Recovery Period |  | 10 years |  |
Pirkey Power Plant Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 63.0 | 0.0 |
Remaining Recovery Period |  | 10 years |  |
Welsh Plant, Units 1 and 3 Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 85.6 | 45.9 |
Welsh Plant, Units 1 and 3 Accelerated Depreciation [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 85.6 | 45.9 |
COVID-19 - Virginia [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 7.0 | 6.8 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 27.2 | 9.3 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.1 | 0.1 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 2.5 | 2.4 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 55.6 | 56.0 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 13.4 | 9.5 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 1.1 | 3.6 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 2.0 | 3.6 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.1 | 0.3 |
Other Regulatory Assets Pending Final Regulatory Approval [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 16.0 | 18.4 |
Storm Related Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 8.4 | 17.4 |
Remaining Recovery Period |  | 2 years |  |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 407.1 | 298.3 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 26.7 | 22.4 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 72.6 | 53.7 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 21.6 | 0.0 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 33.8 | 3.8 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 25.5 | 13.9 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 151.5 | 148.0 |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 11.9 | 25.4 |
Remaining Recovery Period |  | 2 years |  |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 8.5 | 12.8 |
Remaining Recovery Period |  | 2 years |  |
Storm Related Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 3.4 | 12.6 |
Remaining Recovery Period |  | 2 years |  |
Plant Retirement Costs - Asset Retirement Obligation Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 110.6 | 110.2 |
Remaining Recovery Period |  | 20 years |  |
Plant Retirement Costs - Asset Retirement Obligation Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.9 | 25.9 |
Plant Retirement Costs - Asset Retirement Obligation Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 25.9 | 25.9 |
Plant Retirement Costs - Asset Retirement Obligation Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 308.5 | 297.9 |
Remaining Recovery Period |  | 20 years |  |
Plant Retirement Costs - Asset Retirement Obligation Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 303.1 | 293.1 |
Remaining Recovery Period |  | 15 years |  |
Vegetation Management Program [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 5.2 | 5.2 |
Vegetation Management Program [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 12.1 | 17.4 |
Remaining Recovery Period |  | 3 years |  |
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [18] | $ 689.9 | 715.4 |
Remaining Recovery Period |  | 24 years |  |
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 75.6 | 110.0 |
Remaining Recovery Period |  | 21 years |  |
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 147.0 | 170.8 |
Remaining Recovery Period |  | 6 years |  |
Plant Retirement Costs - Unrecovered Plant [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [19] | $ 240.6 | 227.6 |
Remaining Recovery Period |  | 24 years |  |
Plant Retirement Costs - Unrecovered Plant, Arkansas [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 13.1 | 13.7 |
Remaining Recovery Period |  | 20 years |  |
Plant Retirement Costs - Unrecovered Plant, Arkansas [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 21.1 | 0.0 |
Remaining Recovery Period |  | 5 years |  |
Plant Retirement Costs - Unrecovered Plant, Arkansas [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 21.1 | 0.0 |
Remaining Recovery Period |  | 5 years |  |
Plant Retirement Costs - Unrecovered Plant, Texas [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 51.7 | 51.9 |
Remaining Recovery Period |  | 24 years |  |
Plant Retirement Costs - Unrecovered Plant, Texas [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 51.7 | 51.9 |
Remaining Recovery Period |  | 24 years |  |
Meter Replacement Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 34.2 | 44.9 |
Remaining Recovery Period |  | 5 years |  |
Meter Replacement Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 16.1 | 22.7 |
Remaining Recovery Period |  | 4 years |  |
Meter Replacement Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 18.1 | 22.2 |
Remaining Recovery Period |  | 5 years |  |
Ohio Distribution Decoupling [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 19.5 | 41.6 |
Remaining Recovery Period |  | 2 years |  |
Ohio Distribution Decoupling [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 19.5 | 41.6 |
Remaining Recovery Period |  | 2 years |  |
Ohio Basic Transmission Cost Rider [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 14.3 | 5.2 |
Remaining Recovery Period |  | 2 years |  |
Environmental Controls Projects [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 33.9 | 36.2 |
Remaining Recovery Period |  | 18 years |  |
Environmental Controls Projects [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 23.9 | 25.2 |
Remaining Recovery Period |  | 18 years |  |
Environmental Controls Projects [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 10.0 | 11.0 |
Remaining Recovery Period |  | 10 years |  |
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 56.6 | 66.6 |
Remaining Recovery Period |  | 6 years |  |
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 56.6 | 66.6 |
Remaining Recovery Period |  | 6 years |  |
Cook Plant Uprate Project [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.3 | 27.7 |
Remaining Recovery Period |  | 11 years |  |
Cook Plant Uprate Project [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.3 | 27.7 |
Remaining Recovery Period |  | 11 years |  |
Advanced Metering System [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 0.0 | 10.6 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 102.9 | 119.9 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 1.4 | 2.1 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 0.4 | 0.4 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 11.9 | 6.0 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 9.1 | 9.8 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 6.8 | 5.2 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 118.3 | 119.2 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 4.3 | 4.3 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 16.0 | 14.2 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 22.9 | 18.2 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 11.0 | 14.4 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 20.1 | 18.8 |
Other Regulatory Assets Approved for Recovery [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 32.5 | 18.8 |
Vegetation Management [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.8 | 29.3 |
Remaining Recovery Period |  | 3 years |  |
Asset Retirement Obligation - Louisiana [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 11.8 | 10.3 |
Deferred Cook Plant Life Cycle Management Project Costs [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 12.1 | 13.1 |
Remaining Recovery Period |  | 12 years |  |
Cook Plant Study Costs - Indiana [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 8.7 | 9.4 |
Remaining Recovery Period |  | 13 years |  |
Cook Plant Turbine [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 9.0 | 9.7 |
Remaining Recovery Period |  | 16 years |  |
Pension Costs [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 0.0 | 27.6 |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 975.4 | 689.3 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 173.2 | 119.0 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 108.3 | 62.7 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 26.9 | 0.0 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 142.7 | 83.3 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 55.2 | 22.9 |
Remaining Recovery Period |  | 12 years |  |
Pension Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 96.2 | 73.8 |
Remaining Recovery Period |  | 12 years |  |
Unamortized Loss on Reacquired Debt [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 104.1 | 111.6 |
Remaining Recovery Period |  | 26 years |  |
Unamortized Loss on Reacquired Debt [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 74.4 | 78.2 |
Remaining Recovery Period |  | 23 years |  |
Unamortized Loss on Reacquired Debt [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 12.9 | 14.2 |
Remaining Recovery Period |  | 26 years |  |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 11.9 | 14.5 |
Remaining Recovery Period |  | 2 years |  |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 15.8 | 17.8 |
Remaining Recovery Period |  | 4 years |  |
Unrealized Loss on Forward Commitments [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 40.1 | 100.8 |
Remaining Recovery Period |  | 10 years |  |
Unrealized Loss on Forward Commitments [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 40.0 | 92.1 |
Remaining Recovery Period |  | 10 years |  |
Virginia Transmission Rate Adjustment Clause [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 18.7 | 37.2 |
Remaining Recovery Period |  | 2 years |  |
Virginia Transmission Rate Adjustment Clause [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 18.7 | 37.2 |
Remaining Recovery Period |  | 2 years |  |
Vegetation Management Program - West Virginia [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 13.7 | 11.9 |
Remaining Recovery Period |  | 2 years |  |
Cook Nuclear Plant Refueling Outage Levelization [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 81.2 | 32.0 |
Remaining Recovery Period |  | 3 years |  |
Cook Nuclear Plant Refueling Outage Levelization [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 81.2 | 32.0 |
Remaining Recovery Period |  | 3 years |  |
PJM/SPP Annual Formula Rate True Up [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 21.8 | 18.0 |
Remaining Recovery Period |  | 2 years |  |
PJM/SPP Annual Formula Rate True Up [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 7.2 | 8.5 |
Remaining Recovery Period |  | 2 years |  |
Postemployment Benefits [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 32.1 | 32.5 |
Remaining Recovery Period |  | 3 years |  |
Postemployment Benefits [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 13.7 | 13.3 |
Remaining Recovery Period |  | 3 years |  |
Postemployment Benefits [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 7.7 | 9.0 |
Remaining Recovery Period |  | 3 years |  |
Postemployment Benefits [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 6.2 | 6.2 |
Remaining Recovery Period |  | 3 years |  |
OVEC Purchased Power [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 47.1 | 14.8 |
Remaining Refund Period |  | 2 years |  |
OVEC Purchased Power [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 47.1 | 14.8 |
Remaining Refund Period |  | 2 years |  |
Fuel and Purchased Power Adjustment Rider [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 76.3 | 40.8 |
Remaining Recovery Period |  | 2 years |  |
PJM Costs and Off-system Sales Margin Sharing - Indiana [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 34.2 | 0.0 |
Remaining Refund Period |  | 2 years |  |
PJM Costs and Off-system Sales Margin Sharing - Indiana [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 34.2 | 0.0 |
Remaining Refund Period |  | 2 years |  |
PJM Costs and Off-system Sales Margin Sharing - Indiana [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 0.0 | 15.1 |
Other Regulatory Liabilities Pending Final Regulatory Determination [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 4.1 | 2.3 |
Other Regulatory Liabilities Pending Final Regulatory Determination [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 1.8 | 0.0 |
Other Regulatory Liabilities Pending Final Regulatory Determination [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 0.2 | 0.2 |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 277.0 | 468.0 |
Remaining Refund Period |  | 6 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 16.0 | 26.0 |
Remaining Refund Period |  | 6 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 19.0 | 84.0 |
Remaining Refund Period |  | 6 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 42.0 | 90.0 |
Remaining Refund Period |  | 6 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 162.0 | 191.0 |
Remaining Refund Period |  | 6 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 21.0 | 46.0 |
Remaining Refund Period |  | 2 years |  |
Excess ADIT that is Not Subject to Rate Normalization Requirements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 7.0 | 7.0 |
Remaining Refund Period |  | 1 year |  |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [20] | $ 3,392.4 | 3,229.9 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [21] | 766.8 | 744.7 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [22] | 358.8 | 271.4 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [23] | 713.5 | 703.3 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [24] | 170.7 | 179.7 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [25] | 466.5 | 467.6 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [26] | 316.3 | 300.2 |
Asset Removal Costs [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [27] | 481.2 | 461.3 |
Deferred Investment Tax Credits [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 0.3 | 0.3 |
Remaining Refund Period |  | 31 years |  |
Deferred Investment Tax Credits [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 237.3 | 248.5 |
Remaining Refund Period |  | 34 years |  |
Deferred Investment Tax Credits [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 17.4 | 22.4 |
Remaining Refund Period |  | 28 years |  |
Deferred Investment Tax Credits [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 48.2 | 50.8 |
Remaining Refund Period |  | 22 years |  |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 9.5 | 16.2 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 4.3 | 4.8 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 3.0 | 7.0 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 2.2 | 2.4 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 86.9 | 62.6 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 12.7 | 7.9 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 11.0 | 6.6 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 8.5 | 13.9 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 7.8 | 0.4 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 13.2 | 4.3 |
Other Regulatory Liabilities Approved for Payment [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | 7.7 | 13.0 |
Excess Nuclear Decommissioning Funding [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [28] | 1,318.5 | 1,939.7 |
Excess Nuclear Decommissioning Funding [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [29] | 1,318.5 | 1,939.7 |
PJM Transmission Enhancement Refund [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 34.1 | 45.5 |
Remaining Refund Period |  | 3 years |  |
PJM Transmission Enhancement Refund [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 9.8 | 13.0 |
Remaining Refund Period |  | 3 years |  |
PJM Transmission Enhancement Refund [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 14.7 | 19.6 |
Remaining Refund Period |  | 3 years |  |
Transition and Restoration Charges [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 29.4 | 26.3 |
Remaining Refund Period |  | 7 years |  |
Transition and Restoration Charges [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 29.4 | 26.3 |
Remaining Refund Period |  | 7 years |  |
2017-2019 Virginia Triennial Revenue Provision [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 39.1 | 41.6 |
Remaining Refund Period |  | 26 years |  |
2017-2019 Virginia Triennial Revenue Provision [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 39.1 | 41.6 |
Remaining Refund Period |  | 26 years |  |
2017-2019 Virginia Triennial Revenue Provision [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 30.1 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
2017-2019 Virginia Triennial Revenue Provision [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 30.1 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Spent Nuclear Fuel [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [28] | $ 45.8 | 49.5 |
Spent Nuclear Fuel [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [29] | 45.8 | 49.5 |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 28.6 | 28.6 |
Remaining Refund Period |  | 2 years |  |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 23.6 | 22.5 |
Remaining Refund Period |  | 2 years |  |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 41.7 | 40.8 |
Remaining Recovery Period |  | 4 years |  |
Peak Demand Reduction/Energy Efficiency [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 10.3 | 2.8 |
Remaining Recovery Period |  | 2 years |  |
Ohio Enhanced Service Reliability Plan [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 33.3 | 9.5 |
Remaining Recovery Period |  | 2 years |  |
Ohio Enhanced Service Reliability Plan [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 33.3 | 9.5 |
Remaining Recovery Period |  | 2 years |  |
Smart Grid Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.4 | 19.3 |
Remaining Recovery Period |  | 2 years |  |
Smart Grid Costs [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 25.4 | 19.3 |
Remaining Recovery Period |  | 2 years |  |
Dolet Hills Generating Station and Related Fuel Operations | Southwestern Electric Power Co [Member] |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Share of Net Investment in Dolet Hills Power Station |  | $ 112.0 |  |
Amount of Dolet Hills Fuel Costs Approved to Recover |  | 20.0 |  |
Approved Deferral of Dolet Hills Fuel Costs |  | 32.0 |  |
Pirkey Power Plant and Related Fuel Operations | Southwestern Electric Power Co [Member] |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Share of Net Investment in Pirkey Power Plant |  | 215.0 |  |
Pirkey Power Plant and Sabine Unbilled Fixed Costs |  | 43.0 |  |
Dolet Hills Power Station [Member] | Southwestern Electric Power Co [Member] | TEXAS |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Asset Impairments and Other Related Charges |  | 12.0 |  |
Dolet Hills Power Station [Member] | Southwestern Electric Power Co [Member] | Arkansas |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Asset Impairments and Other Related Charges |  | 2.0 |  |
Unrealized Gain on Forward Commitments [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 45.2 | 40.4 |
Remaining Refund Period |  | 2 years |  |
Unrealized Gain on Forward Commitments [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 34.5 | 28.2 |
Remaining Refund Period |  | 2 years |  |
Welsh Plant Unit 2 | Southwestern Electric Power Co [Member] |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Impairment Charge Welsh Plant, Unit 2 |  | $ 7.0 |  |
February 2021 Severe Storm Fuel Costs |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Proceeds For Securitzation Bonds |  | 687.0 |  |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets | [30] | $ 95.8 | 62.7 |
Remaining Recovery Period |  | 1 year |  |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Current Regulatory Assets | [31] | $ 95.8 | 62.7 |
Remaining Recovery Period |  | 1 year |  |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 84.6 | 367.5 |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [31] | 84.6 | 367.5 |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [32] | $ 148.6 | 679.3 |
Remaining Recovery Period |  | 5 years |  |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [33] | $ 0.0 | 679.3 |
February 2021 Severe Storm Fuel Costs | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets | [31] | $ 148.6 | 0.0 |
Remaining Recovery Period |  | 5 years |  |
Dolet Hills Power Station Fuel Costs - Louisiana | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 32.0 | 30.9 |
Dolet Hills Power Station Fuel Costs - Louisiana | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 32.0 | 30.9 |
Texas Transmission Cost Recovery Factor | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 3.8 | 30.6 |
Remaining Recovery Period |  | 2 years |  |
Texas Transmission Cost Recovery Factor | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 3.8 | 30.6 |
Remaining Recovery Period |  | 2 years |  |
Texas Retail Electric Provider Bad Debt Expense | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 4.1 | 4.1 |
Environmental Compliance Costs | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 4.3 | 13.7 |
Remaining Recovery Period |  | 2 years |  |
Environmental Cost Rider - Indiana | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 0.0 | 10.6 |
Ohio Economic Development Rider | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 1.1 | 10.1 |
Remaining Recovery Period |  | 2 years |  |
PJM Load Service Entity Formula Rate True-Up | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 0.0 | 7.5 |
Dolet Hills Power Station Fuel Costs - Arkansas | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 8.9 | 13.0 |
Remaining Recovery Period |  | 4 years |  |
2020-2022 Virginia Triennial Revenue Provision [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 37.9 | 15.1 |
2020-2022 Virginia Triennial Revenue Provision [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 37.9 | 15.1 |
Long-term Under-recovered Fuel Costs - Oklahoma [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 252.7 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Long-term Under-recovered Fuel Costs - Oklahoma [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 252.7 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Long-term Under-recovered Fuel Costs - Virginia [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 223.3 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Long-term Under-recovered Fuel Costs - Virginia [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 223.3 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Louisiana Jurisdiction [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 45.1 | 0.0 |
Remaining Recovery Period |  | 10 years |  |
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 45.1 | 0.0 |
Remaining Recovery Period |  | 10 years |  |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [34],[35] | $ 2,504.5 | 2,792.0 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [36],[37] | 431.6 | 445.3 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [38],[39] | 355.8 | 371.6 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [40],[41] | 291.3 | 432.9 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [42],[43] | 168.6 | 182.6 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Ohio Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [44],[45] | 451.9 | 480.6 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [46],[47] | 380.1 | 423.8 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [48],[49] | 327.6 | 330.2 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [34] | 149.7 | 262.2 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [36] | 13.0 | 13.0 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | AEP Transmission Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [38] | 8.7 | 8.7 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [40] | 30.5 | 4.5 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [42],[50] | (87.7) | 0.0 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | Public Service Co Of Oklahoma [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [46] | 51.3 | 56.2 |
Income Taxes, Net [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Pending Final Regulatory Determination [Member] | Southwestern Electric Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities | [48] | 7.0 | 0.0 |
Rockport Plant, Unit 2 Accelerated Depreciation for Leasehold Improvements [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 53.8 | 4.2 |
Remaining Refund Period |  | 6 years |  |
Renewable Energy Surcharge - Michigan [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 23.2 | 14.9 |
Remaining Refund Period |  | 2 years |  |
Renewable Energy Surcharge - Michigan [Member] | Regulatory Liabilities Currently Paying a Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Indiana Michigan Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 23.2 | 14.9 |
Remaining Refund Period |  | 2 years |  |
Over-recovered Fuel Costs - Ohio [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 32.2 | 15.2 |
Remaining Refund Period |  | 10 years |  |
Texas Mobile Generation Lease Payments [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] | AEP Texas Inc. [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 17.6 | 0.0 |
Virginia Clean Economy Act [Member] | Regulatory Assets Currently Not Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 16.7 | 0.0 |
Remaining Recovery Period |  | 2 years |  |
Over-recovered Deferred Wind Costs - Virginia [Member] | Regulatory Liabilities Currently Not Paying Return [Member] | Regulatory Liabilities Approved for Payment [Member] | Appalachian Power Co [Member] |  |  |  |
Regulatory Liabilities |  |  |  |
Noncurrent Regulatory Liabilities |  | $ 13.6 | 8.4 |
Remaining Refund Period |  | 2 years |  |
Plant Retirement Costs - Unrecovered Plant, Welsh Plant, Unit 2 [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Approved for Recovery [Member] | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 35.2 | $ 0.0 |
Remaining Recovery Period |  | 10 years |  |
February 2021 Severe Storm Fuel Costs | Public Service Co Of Oklahoma [Member] |  |  |  |
Effects of Regulation Textuals [Abstract] |  |  |  |
Proceeds For Securitzation Bonds |  | $ 687.0 |  |
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 329.0 |  |
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Arkansas | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | 75.0 |  |
February 2021 Severe Storm Fuel Costs | Southwestern Electric Power Co [Member] | Louisiana Jurisdiction [Member] | Regulatory Assets Currently Earning Return [Member] | Regulatory Assets Pending Final Regulatory Approval [Member] |  |  |  |
Regulatory Assets |  |  |  |
Noncurrent Regulatory Assets |  | $ 122.0 |  |
[1] | Includes ARO related to Sabine and DHLC.
[2] | Includes ARO related to asbestos removal.
[3] | Includes ARO related to ash disposal facilities.
[4] | Includes ARO related to nuclear decommissioning costs for the Cook Plant of $2 billion and $1.93 billion as of December 31, 2022 and 2021, respectively.
[5] | Includes ARO related to solar farms.
[6] | Includes ARO related to wind 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] | Includes Northeastern Plant, Unit 4, which was retired in 2016. Removal of Northeastern Plant, Unit 4, will be performed with Northeastern Plant, Unit 3, after retirement.
[9] | Northeastern Plant, Unit 3 is currently being recovered through 2040.
[10] | Represents the amount of annual depreciation that has been collected from customers over the prior 12-month period.
[11] | Pirkey Plant is currently being recovered through 2032 in the Louisiana jurisdiction and through 2045 in the Arkansas and Texas jurisdictions.
[12] | Includes Welsh Plant, Unit 2, which was retired in 2016. Removal of Welsh Plant, Unit 2, will be performed with Welsh Plant, Units 1 and 3, after retirement.
[13] | Unit 1 is being recovered through 2027 in the Louisiana jurisdiction and through 2037 in the Arkansas and Texas jurisdictions. Unit 3 is being recovered through 2032 in the Louisiana jurisdiction and through 2042 in the Arkansas and Texas jurisdictions.
[14] | 2022 amount includes Louisiana jurisdiction.
[15] | 2022 amount includes Arkansas and Texas jurisdictions. 2021 amount includes Arkansas, Louisiana and Texas jurisdictions.
[16] | 2022 amount includes the FERC jurisdiction. 2021 amounts include Arkansas, Louisiana and FERC jurisdictions.
[17] | 2022 amount includes the FERC jurisdiction. 2021 amounts include Arkansas, Louisiana and FERC jurisdictions.
[18] | Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.
[19] | Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.
[20] | Relieved as removal costs are incurred.
[21] | Relieved as removal costs are incurred.
[22] | Relieved as removal costs are incurred.
[23] | Relieved as removal costs are incurred.
[24] | Relieved as removal costs are incurred.
[25] | Relieved as removal costs are incurred.
[26] | Relieved as removal costs are incurred.
[27] | Relieved as removal costs are incurred.
[28] | Relieved when plant is decommissioned.
[29] | Relieved when plant is decommissioned.
[30] | In 2022, Unrecovered Winter Storm Costs in the Arkansas and Texas jurisdictions were approved for recovery by the APSC and PUCT. As of December 31, 2022, Unrecovered Winter Storm Fuel Costs in the Louisiana jurisdiction are pending final regulatory approval with the LPSC. The current asset balance represents amounts expected to be recovered in the Arkansas, Louisiana and Texas jurisdiction over the next 12 months. See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.
[31] | In 2022, Unrecovered Winter Storm Costs in the Arkansas and Texas jurisdictions were approved for recovery by the APSC and PUCT. As of December 31, 2022, Unrecovered Winter Storm Fuel Costs in the Louisiana jurisdiction are pending final regulatory approval with the LPSC. The current asset balance represents amounts expected to be recovered in the Arkansas, Louisiana and Texas jurisdiction over the next 12 months. See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.
[32] | In February 2022, the OCC approved PSO’s securitization of the Unrecovered Winter Storm Fuel Costs. In September 2022, PSO received proceeds of $687 million from the ODFA which issued ratepayer-backed securitization bonds for the purpose of reimbursing PSO for extraordinary fuel costs and purchases of electricity incurred during the February 2021 severe winter weather event, which were previously recorded as Regulatory Assets on PSO’s balance sheet. See “February 2021 Severe Winter Weather Impacts in SPP” section of PSO Rate Matters in Note 4 for additional information.
[33] | In February 2022, the OCC approved PSO’s securitization of the Unrecovered Winter Storm Fuel Costs. In September 2022, PSO received proceeds of $687 million from the ODFA which issued ratepayer-backed securitization bonds for the purpose of reimbursing PSO for extraordinary fuel costs and purchases of electricity incurred during the February 2021 severe winter weather event, which were previously recorded as Regulatory Assets on PSO’s balance sheet. See “February 2021 Severe Winter Weather Impacts in SPP” section of PSO Rate Matters in Note 4 for additional information.
[34] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[35] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $277 million and $468 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 6 years.
[36] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[37] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets.
[38] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[39] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $16 million and $26 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 6 years.
[40] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[41] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $19 million and $84 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 6 years.
[42] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[43] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $42 million and $90 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 6 years.
[44] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[45] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $162 million and $191 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 6 years.
[46] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[47] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $21 million and $46 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 2 years.
[48] | Predominately pays a return due to the inclusion of Excess ADIT in rate base.
[49] | Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $7 million and $7 million for the years ended December 31, 2022 and 2021, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2022 is to be refunded over 1 year.
[50] | Represents an income tax related regulatory asset, which is presented within net regulatory liabilities on the balance sheet.

X
- Definition The amount of accelerated depreciation as a regulatory asset for plants to be retired. + References No definition available. + Details
Name: | aep_AcceleratedDepreciation
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of Dolet Hills Fuel Costs Approved to Recover in 2021. + References No definition available. + Details
Name: | aep_AmountOfDoletHillsFuelCostsApprovedToRecover
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Approved Deferral of Dolet Hills Fuel Costs in 2021 + References No definition available. + Details
Name: | aep_ApprovedDeferralOfDoletHillsFuelCosts
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The regulatory liability recorded for cost of removal. + References No definition available. + Details
Name: | aep_CostofRemovalRegulatoryLiability
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Effects of Regulation Textuals [Abstract] + References No definition available. + Details
Name: | aep_EffectsofRegulationTextualsAbstract
Namespace Prefix: | aep_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Impairment recorded due to lack of return on Welsh Plant Unit 2. + References No definition available. + Details
Name: | aep_ImpairmentChargeWelshPlantUnit2
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Net Under-Recovered Fuel Costs + References No definition available. + Details
Name: | aep_NetUnderRecoveredFuelCosts
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Pirkey Power Plant and Sabine unbilled fixed costs that will be billed to SWEPCo prior to closure. + References No definition available. + Details
Name: | aep_PirkeyPowerPlantAndSabineUnbilledFixedCosts
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Proceeds received for ODFA for ratepayer-backed securitization bonds. + References No definition available. + Details
Name: | aep_ProceedsForSecuritzationBonds
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Recommended Dolet Hills Fuel Disallowance + References No definition available. + Details
Name: | aep_RecommendedDoletHillsFuelDisallowance
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Regulated Generating Unit to be Retired [Abstract] + References No definition available. + Details
Name: | aep_RegulatedGeneratingUnittobeRetiredAbstract
Namespace Prefix: | aep_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Regulatory assets are comprised Abstract. + References No definition available. + Details
Name: | aep_RegulatoryAssetsAreComprisedAbstract
Namespace Prefix: | aep_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Regulatory liabilities are comprised Abstract. + References No definition available. + Details
Name: | aep_RegulatoryLiabilitiesAreComprisedAbstract
Namespace Prefix: | aep_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition SWEPCo's share of the net investment in Pirkey Power Plant + References No definition available. + Details
Name: | aep_ShareOfNetInvestmentInPirkeyPowerPlant
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition SWEPCo's share of the net investment in Dolet Hills Power Station. + References No definition available. + Details
Name: | aep_ShareofNetInvestmentinDoletHillsPowerStation
Namespace Prefix: | aep_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(14)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(4) -URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
Name: | us-gaap_AssetRetirementObligationRevisionOfEstimate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 + Details
Name: | us-gaap_Depreciation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Description of the facts and circumstances leading to the completed or expected disposal, and the manner and timing of that disposal. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.Z.5.Q2) -URI https://asc.fasb.org/extlink&oid=26872618&loc=d3e7384-122677 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI https://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760 + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationDescriptionAndTimingOfDisposal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 + Details
Name: | us-gaap_OtherAssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(a)(5)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_OtherInventorySupplies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 360 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124429447&loc=SL124453093-239630 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766 + Details
Name: | us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_RegulatoryAssetAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortization period for the recovery of regulatory liability, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_RegulatoryLiabilityAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 405 -Section 25 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
Name: | us-gaap_RegulatoryLiabilityCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.24) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_RegulatoryLiabilityNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_SecuredDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=aep_AEPTexasInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_AEPTransmissionCoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_AppalachianPowerCoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_IndianaMichiganPowerCoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_OhioPowerCoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_PublicServiceCoOfOklahomaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aep_SouthwesternElectricPowerCoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=aep_RegulatoryLiabilitiesBeingPaidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryLiabilityAxis=aep_RegulatoryLiabilitiesNotYetBeingPaidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryLiabilitiesAxis=aep_RegulatoryLiabilitiesCurrentlyPayingReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryLiabilitiesAxis=aep_RegulatoryLiabilitiesCurrentlyNotPayingReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=aep_RegulatoryAssetsNotYetBeingRecoveredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=aep_RegulatoryAssetsBeingRecoveredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetsCurrentlyReturnAxis=aep_RegulatoryAssetsCurrentlyEarningReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetsCurrentlyReturnAxis=aep_RegulatoryAssetsCurrentlyNotEarningReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_NortheasternPlantUnit3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=aep_GeneratingUnitsProbableofAbandonmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsGeneratingStationUnitNo1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PirkeyGeneratingStationUnitNo1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_WelshPlantUnit1and3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_DeferredFuelCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=aep_IndianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=aep_MichiganMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsPowerStationAcceleratedDepreciationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_KentuckyDeferredPurchasePowerExpensesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantLouisianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PirkeyPowerPlantAcceleratedDepreciationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=aep_LouisianaJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_WelshPlantUnits1And3AcceleratedDepreciationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_COVID19VirginiaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OtherRegulatoryAssetsNotYetBeingRecoveredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_StormCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_AssetRetirementObligationRelatedtoRetiredPlantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_VegetationManagementProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantArkansasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantTexasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_MeterReplacementCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DistributionDecouplingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OhioBasicTransmissionCostRiderMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_EnvironmentalControlsProjectsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_RockportPlantDrySorbentInjectionSystemIndianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_CookPlantUprateProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OverRecoveryofCostsRelatedtoAdvancedMeteringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OtherRegulatoryAssetsBeingRecoveredMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_VegetationManagementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_AssetRetirementObligationLouisianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_MichiganDeferredCookPlantLifeCycleManagementProjectCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_CookPlantStudyCostsIndianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_CookPlantTurbineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_PensionCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_LossOnReacquiredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PeakDemandEnergyEfficiencyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_UnrealizedLossOnForwardCommitmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_VirginiaTransmissionRateAdjustmentClauseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_VegetationManagementProgramWestVirginiaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_CookNuclearPlantRefuelingOutageLevelizationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PJMSPPAnnualFormulaRateTrueUpMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PostemploymentBenefitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OVECPurchasedPowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_FuelAndPurchasedPowerAdjustmentRiderMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PJMCostsandOffsystemSalesMarginSharingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OtherRegulatoryLiabilitiesNotYetBeingPaidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_ExcessADITthatisNotSubjecttoRateNormalizationRequirementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_AssetRemovalCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DeferredInvestmentTaxCreditsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OtherRegulatoryLiabilitiesBeingPaidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_ExcessAssetRetirementObligationsForNuclearDecommissioningLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PJMTransmissionEnhancementRefundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_TransitionAndRestorationChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_A20172019VirginiaTriennialRevenueProvisionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_SpentNuclearFuelLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_EnergyEfficiencypeakDemandReductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_EnhancedServiceReliabilityPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_SmartGridCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsPowerStationAndRelatedFuelOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PirkeyPowerPlantAndRelatedFuelOperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsPowerStationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=stpr_TX
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=aep_ArkansasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_UnrealizedGainOnForwardCommitmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_WelshPlantUnit2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_February2021SevereStormFuelCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsPowerStationFuelCostsLouisianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_TexasTransmissionCostRecoveryFactorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_TexasRetailElectricProviderBadDebtExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_EnvironmentalComplianceCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_RockportPlantUnit2SelectiveCatalyticReductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OhioEconomicDevelopmentRiderMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PJMLoadServiceEntityFormulaRateTrueUpMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_DoletHillsPowerStationFuelCostsArkansasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_A20202022VirginiaTriennialRevenueProvisionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_LongTermUnderRecoveredFuelCostsOklahomaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_LongTermUnderRecoveredFuelCostsVirginiaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantDoletHillsPowerStationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_IncomeTaxesNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_RockportPlantUnit2AcceleratedDepreciationForLeaseholdImprovementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_RenewableEnergySurchargeMichiganMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OverRecoveredFuelCostsOhioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_TexasMobileGenerationLeasePaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_VirginiaCleanEconomyActMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_OverRecoveredDeferredWindCostsVirginiaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=aep_PlantRetirementCostsUnrecoveredPlantWelshPlantUnit2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_BaseRateAxis=aep_February2021SevereStormFuelCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatoryAssetReturnDisclosureAxis=aep_RegulatoryAssetsCurrentlyEarningReturnMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aep_RegulatedStatusAxis=aep_RegulatoryAssetsPendingFinalRegulatoryApprovalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |