Investments - Amortized Cost and Fair Value of Trust Investments (Details) - SCE - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Fair Value Measurements
Fair Values	$ 4,231	$ 4,286
Deferred income taxes related to unrealized gains	361	373
Total debt securities and other
Fair Value Measurements
Amortized Costs	2,420	2,428
Fair Values	2,656	2,655
Municipal bonds
Fair Value Measurements
Amortized Costs	759	729
Fair Values	897	860
Government and agency securities
Fair Value Measurements
Amortized Costs	1,212	1,201
Fair Values	1,384	1,341
Corporate bonds
Fair Value Measurements
Amortized Costs	332	346
Fair Values	383	392
Short-term investments and receivables/payables
Fair Value Measurements
Amortized Costs	117	152
Fair Values	(8)	62
Repurchase Agreements
Fair Value Measurements
Fair Values	9	18
Equity securities
Fair Value Measurements
Fair Values	$ 1,575	$ 1,631