v3.26.3
BUSINESS SEGMENTS - Schedule of AEP's Reportable Segment Information (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Revenues from:          
Total Revenues $ 6,832 $ 6,011 $ 18,297 $ 16,561  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 2,087 1,981 5,808 5,375  
Other Operation and Maintenance 1,475 1,203 3,894 3,202  
Asset Impairments and Other Related Charges 0 0 31 0  
Depreciation and Amortization 1,025 879 2,842 2,566  
Taxes Other Than Income Taxes 433 426 1,303 1,213  
Allowance for Equity Funds Used During Construction 81 59 226 173  
Interest Expense 606 509 1,743 1,493  
Income Tax Expense (Benefit) 125 139 221 13  
Equity Earnings of Unconsolidated Subsidiaries 25 21 79 80  
Other Segment Items 0 (18) (14) (46)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 1,187 972 2,774 2,998  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 1,187 972 2,774 2,998  
Gross Property Additions 4,580 2,279 11,501 7,658  
Total Assets 125,695   125,695   $ 114,460
Investments in Equity Method Investees 1,404   1,404   1,252
Nonrelated Party          
Revenues from:          
Total Revenues 6,832 6,011 18,297 16,561  
Related Party          
Revenues from:          
Total Revenues 0 0 0 0  
Operating Segments          
Revenues from:          
Total Revenues 7,434 6,561 20,055 18,302  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 2,171 2,057 6,046 5,595  
Other Operation and Maintenance 1,996 1,710 5,428 4,806  
Asset Impairments and Other Related Charges     31    
Depreciation and Amortization 1,030 884 2,856 2,581  
Taxes Other Than Income Taxes 426 421 1,281 1,195  
Allowance for Equity Funds Used During Construction 81 59 226 173  
Interest Expense 472 390 1,343 1,123  
Income Tax Expense (Benefit) 166 109 312 84  
Equity Earnings of Unconsolidated Subsidiaries 24 21 74 69  
Other Segment Items (18) (20) (49) (53)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 1,296 1,090 3,107 3,213  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 1,296 1,090 3,107 3,213  
Gross Property Additions 4,446 2,285 11,102 7,627  
Total Assets 124,535   124,535   112,772
Investments in Equity Method Investees 1,122   1,122   1,081
Operating Segments | Nonrelated Party          
Revenues from:          
Total Revenues 6,831 6,005 18,288 16,536  
Operating Segments | Related Party          
Revenues from:          
Total Revenues 603 556 1,767 1,766  
Operating Segments | VIU          
Revenues from:          
Total Revenues 4,001 3,586 10,561 9,739  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 1,121 1,168 3,096 3,164  
Other Operation and Maintenance 1,118 998 3,190 2,863  
Asset Impairments and Other Related Charges     31    
Depreciation and Amortization 659 547 1,787 1,594  
Taxes Other Than Income Taxes 146 142 433 398  
Allowance for Equity Funds Used During Construction 25 20 69 52  
Interest Expense 280 219 789 621  
Income Tax Expense (Benefit) 20 (25) (92) (117)  
Equity Earnings of Unconsolidated Subsidiaries 0 0 1 1  
Other Segment Items (15) (21) (46) (66)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 697 578 1,443 1,335  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 697 578 1,443 1,335  
Gross Property Additions 2,442 1,203 6,050 4,356  
Total Assets 67,958   67,958   61,778
Investments in Equity Method Investees 8   8   9
Operating Segments | VIU | Nonrelated Party          
Revenues from:          
Total Revenues 3,923 3,511 10,338 9,531  
Operating Segments | VIU | Related Party          
Revenues from:          
Total Revenues 78 75 223 208  
Operating Segments | T&D          
Revenues from:          
Total Revenues 1,868 1,690 5,060 4,666  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 258 264 716 730  
Other Operation and Maintenance 765 624 2,000 1,742  
Asset Impairments and Other Related Charges     0    
Depreciation and Amortization 231 210 658 614  
Taxes Other Than Income Taxes 202 191 592 555  
Allowance for Equity Funds Used During Construction 29 17 82 55  
Interest Expense 119 107 341 318  
Income Tax Expense (Benefit) 51 57 128 142  
Equity Earnings of Unconsolidated Subsidiaries 0 1 0 2  
Other Segment Items (13) (12) (36) (34)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 284 267 743 656  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 284 267 743 656  
Gross Property Additions 1,029 711 3,094 2,079  
Total Assets 32,162   32,162   29,272
Investments in Equity Method Investees 2   2   4
Operating Segments | T&D | Nonrelated Party          
Revenues from:          
Total Revenues 1,853 1,680 5,015 4,638  
Operating Segments | T&D | Related Party          
Revenues from:          
Total Revenues 15 10 45 28  
Operating Segments | AEPTHCo          
Revenues from:          
Total Revenues 615 573 1,823 1,872  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 0 0 0 0  
Other Operation and Maintenance 65 53 175 136  
Asset Impairments and Other Related Charges     0    
Depreciation and Amortization 136 124 397 361  
Taxes Other Than Income Taxes 77 87 254 240  
Allowance for Equity Funds Used During Construction 27 22 75 66  
Interest Expense 71 63 208 179  
Income Tax Expense (Benefit) 69 61 199 (11)  
Equity Earnings of Unconsolidated Subsidiaries 24 20 73 66  
Other Segment Items 29 27 85 86  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 219 200 653 1,013  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 219 200 653 1,013  
Gross Property Additions 878 368 1,782 1,182  
Total Assets 21,285   21,285   19,719
Investments in Equity Method Investees 1,112   1,112   1,068
Operating Segments | AEPTHCo | Nonrelated Party          
Revenues from:          
Total Revenues 133 120 389 391  
Operating Segments | AEPTHCo | Related Party          
Revenues from:          
Total Revenues 482 453 1,434 1,481  
Operating Segments | G&M          
Revenues from:          
Total Revenues 950 712 2,611 2,025  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 792 625 2,234 1,701  
Other Operation and Maintenance 48 35 63 65  
Asset Impairments and Other Related Charges     0    
Depreciation and Amortization 4 3 14 12  
Taxes Other Than Income Taxes 1 1 2 2  
Allowance for Equity Funds Used During Construction 0 0 0 0  
Interest Expense 2 1 5 5  
Income Tax Expense (Benefit) 26 16 77 70  
Equity Earnings of Unconsolidated Subsidiaries 0 0 0 0  
Other Segment Items (19) (14) (52) (39)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 96 45 268 209  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 96 45 268 209  
Gross Property Additions 97 3 176 10  
Total Assets 3,130   3,130   2,003
Investments in Equity Method Investees 0   0   0
Operating Segments | G&M | Nonrelated Party          
Revenues from:          
Total Revenues 922 694 2,546 1,976  
Operating Segments | G&M | Related Party          
Revenues from:          
Total Revenues 28 18 65 49  
Corporate and Other          
Revenues from:          
Total Revenues 38 36 99 110  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation 0 0 0 0  
Other Operation and Maintenance 41 8 106 44  
Asset Impairments and Other Related Charges     0    
Depreciation and Amortization (5) (5) (14) (15)  
Taxes Other Than Income Taxes 1 0 1 1  
Allowance for Equity Funds Used During Construction 0 0 0 0  
Interest Expense 176 140 512 438  
Income Tax Expense (Benefit) (41) 30 (91) (71)  
Equity Earnings of Unconsolidated Subsidiaries 1 0 5 11  
Other Segment Items (24) (19) (77) (61)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic (109) (118) (333) (215)  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted (109) (118) (333) (215)  
Gross Property Additions 170 18 453 54  
Total Assets 7,136   7,136   6,733
Investments in Equity Method Investees 282   282   171
Corporate and Other | Nonrelated Party          
Revenues from:          
Total Revenues 1 6 9 25  
Corporate and Other | Related Party          
Revenues from:          
Total Revenues 37 30 90 85  
Reconciling Adjustments          
Revenues from:          
Total Revenues (640) (586) (1,857) (1,851)  
Purchased Electricity, Fuel and Other Consumables Used for Electric Generation (84) (76) (238) (220)  
Other Operation and Maintenance (562) (515) (1,640) (1,648)  
Asset Impairments and Other Related Charges     0    
Depreciation and Amortization 0 0 0 0  
Taxes Other Than Income Taxes 6 5 21 17  
Allowance for Equity Funds Used During Construction 0 0 0 0  
Interest Expense (42) (21) (112) (68)  
Income Tax Expense (Benefit) 0 0 0 0  
Equity Earnings of Unconsolidated Subsidiaries 0 0 0 0  
Other Segment Items 42 21 112 68  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Basic 0 0 0 0  
EARNINGS (LOSS) ATTRIBUTABLE TO AEP COMMON SHAREHOLDERS, Diluted 0 0 0 0  
Gross Property Additions (36) (24) (54) (23)  
Total Assets (5,976)   (5,976)   (5,045)
Investments in Equity Method Investees 0   0   $ 0
Reconciling Adjustments | Nonrelated Party          
Revenues from:          
Total Revenues 0 0 0 0  
Reconciling Adjustments | Related Party          
Revenues from:          
Total Revenues $ (640) $ (586) $ (1,857) $ (1,851)