Investments - Amortized Cost and Fair Value of Trust Investments (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Fair Value
Fair Values	$ 4,286	$ 4,173
SCE
Fair Value
Fair Values	4,286	4,173
Deferred income taxes related to unrealized gains	373	380
SCE | Total debt securities and other
Fair Value
Amortized Costs	2,428	2,233
Fair Values	2,655	2,515
SCE | Municipal bonds
Fair Value
Amortized Costs	729	636
Fair Values	860	757
SCE | Government and agency securities
Fair Value
Amortized Costs	1,201	1,072
Fair Values	1,341	1,186
SCE | Corporate bonds
Fair Value
Amortized Costs	346	361
Fair Values	392	401
SCE | Short-term investments and receivables/payables
Fair Value
Amortized Costs	152	164
Fair Values	62	171
SCE | Repurchase Agreements
Fair Value
Fair Values	18	38
SCE | Equity securities
Fair Value
Fair Values	$ 1,631	$ 1,658