Government Assistance (Details) - Nuclear PTCs - USD ($) |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Dec. 31, 2025 |
|
| Government Assistance [Line Items] | |||
| Estimated nuclear PTC receivable | $ 125,000,000 | $ 120,000,000 | |
| Estimated nuclear PTCs credits used | 0 | 375,000,000 | |
| Estimated refunds recognized | $ 740,000,000 | $ 1,190,000,000 | |
| Government Assistance, Liability, Statement of Financial Position [Extensible Enumeration] | Other deferred credits and other liabilities | Other deferred credits and other liabilities | |
| Outstanding receivables offset | $ 450,000,000 | ||
| Government assistance, operating income, increase (decrease) | $ 285,000,000 | $ (110,000,000) | |