FINANCING ACTIVITIES - Schedule of Nonutility Money Pool Activity (Details) - AEP TEXAS INC. - USD ($) $ in Millions |
6 Months Ended | |
|---|---|---|
Jun. 30, 2026 |
Dec. 31, 2025 |
|
| Short-Term Debt [Line Items] | ||
| Advances to Affiliates | $ 7 | $ 7 |
| Nonutility | ||
| Short-Term Debt [Line Items] | ||
| Maximum Loans | 7 | |
| Average Loans | 7 | |
| Nonutility | Related Party | ||
| Short-Term Debt [Line Items] | ||
| Advances to Affiliates | $ 7 |