Income Taxes (Rate Reconciliation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Tax Disclosure [Line Items]
Statutory tax rate (as a percent)	21.00%
(Loss) income from operations before income taxes	$ 254	$ 129
Provision for income tax at federal statutory rate of 21%	53	27
Increase in income tax from:
State tax, net of federal benefit	(7)	(13)
Property-related	(83)	(78)
Change related to uncertain tax positions		(15)
Other	1	(5)
Total continuing operations	$ (36)	$ (84)
Effective tax rate (as a percent)	(14.20%)	(65.10%)
SCE
Income Tax Disclosure [Line Items]
(Loss) income from operations before income taxes	$ 299	$ 174
Provision for income tax at federal statutory rate of 21%	63	37
Increase in income tax from:
State tax, net of federal benefit	(4)	(12)
Property-related	(83)	(78)
Change related to uncertain tax positions		(17)
Other		(5)
Total continuing operations	$ (24)	$ (75)
Effective tax rate (as a percent)	(8.00%)	(43.10%)