Asset Retirement Obligations - Nuclear Decommissioning Asset Retirement Obligation Rollforward (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ||
| Accretion expense | $ 174 | $ 158 |
| Net decrease due to changes in, and timing of, estimated future cash flows | 285 | |
| Nuclear Decommissioning | ||
| Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] | ||
| ARO beginning balance | 12,908 | |
| Accretion expense | 165 | |
| Net decrease due to changes in, and timing of, estimated future cash flows | (1,277) | |
| Costs incurred related to decommissioning plants | (4) | |
| ARO ending balance | $ 11,792 | |