Investments (Trust Info) (Details) - SCE - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Investments
Cumulative unrealized holding gains, net of losses	$ 1,500	$ 1,600
Deferred income taxes related to unrealized gains	313	321
Nuclear decommissioning trusts, net of deferred tax	$ 3,600	$ 3,600