PROPERTY, PLANT AND EQUIPMENT (Details) $ in Millions |
9 Months Ended |
|---|---|
|
Sep. 30, 2026
USD ($)
| |
| Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | |
| Beginning Balance | $ 3,712 |
| Accretion Expense | 131 |
| Liabilities Incurred | 11 |
| Liabilities Settled | (72) |
| Revisions in Cash Flow Estimates | 43 |
| Ending Balance | 3,825 |
| PSO | |
| Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | |
| Beginning Balance | 143 |
| Accretion Expense | 7 |
| Liabilities Incurred | 8 |
| Liabilities Settled | (5) |
| Revisions in Cash Flow Estimates | 19 |
| Ending Balance | 172 |
| SOUTHWESTERN ELECTRIC POWER COMPANY | |
| Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | |
| Beginning Balance | 290 |
| Accretion Expense | 12 |
| Liabilities Incurred | 0 |
| Liabilities Settled | (42) |
| Revisions in Cash Flow Estimates | 4 |
| Ending Balance | $ 264 |