Summary of Significant Accounting Policies (Deferred Financing) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Regulatory Assets
Amortization of deferred financing costs charged to interest expense	$ 39	$ 37	$ 34
SCE
Regulatory Assets
Amortization of deferred financing costs charged to interest expense	$ 32	$ 31	$ 29