Investments - Schedule of Amortized Cost and Fair Value of the Trust Investments (Details) - SCE - USD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Fair Value Measurements | ||
| Fair Values | $ 4,324 | $ 4,286 |
| Deferred tax liabilities on net unrealized gains | 398 | 373 |
| Total debt securities and other | ||
| Fair Value Measurements | ||
| Amortized Costs | 2,373 | 2,428 |
| Fair Values | 2,603 | 2,655 |
| Municipal bonds | ||
| Fair Value Measurements | ||
| Amortized Costs | 770 | 729 |
| Fair Values | 921 | 860 |
| Government and agency securities | ||
| Fair Value Measurements | ||
| Amortized Costs | 1,086 | 1,201 |
| Fair Values | 1,263 | 1,341 |
| Corporate bonds | ||
| Fair Value Measurements | ||
| Amortized Costs | 322 | 346 |
| Fair Values | 380 | 392 |
| Short-term investments and receivables/(payables) | ||
| Fair Value Measurements | ||
| Amortized Costs | 195 | 152 |
| Fair Values | 39 | 62 |
| Repurchase Agreements | ||
| Fair Value Measurements | ||
| Fair Values | 120 | 18 |
| Equity securities | ||
| Fair Value Measurements | ||
| Fair Values | $ 1,721 | $ 1,631 |