Income Taxes (Rate Reconciliation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Line Items]
Statutory tax rate (as a percent)	21.00%
Income from operations before income taxes	$ 81	$ 254
Provision for income tax at federal statutory rate of 21%	17	53
(Decrease) increase in income tax from:
State tax, net of federal benefit	(17)	(7)
Property-related	(45)	(83)
Other	(10)	1
Total income tax benefit	$ (55)	$ (36)
Effective tax rate (as a percent)	(67.90%)	(14.20%)
SCE
Income Tax Disclosure [Line Items]
Income from operations before income taxes	$ 133	$ 299
Provision for income tax at federal statutory rate of 21%	28	63
(Decrease) increase in income tax from:
State tax, net of federal benefit	(13)	(4)
Property-related	(45)	(83)
Other	(10)
Total income tax benefit	$ (40)	$ (24)
Effective tax rate (as a percent)	(30.10%)	(8.00%)