FINANCING ACTIVITIES - Schedule of Proceeds on Sale of Receivables to AEP Credit (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| APCo | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Proceeds from sale of receivables to AEP Credit | $ 452 | $ 495 | $ 1,411 | $ 1,530 |
| I&M | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Proceeds from sale of receivables to AEP Credit | 723 | 683 | 2,068 | 1,813 |
| OPCo | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Proceeds from sale of receivables to AEP Credit | 1,070 | 927 | 2,799 | 2,523 |
| PSO | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Proceeds from sale of receivables to AEP Credit | 809 | 659 | 1,722 | 1,466 |
| SWEPCo | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Proceeds from sale of receivables to AEP Credit | $ 644 | $ 550 | $ 1,539 | $ 1,434 |