Supplemental Cash Flows Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash payments (receipts):
Interest, net of amounts capitalized	$ 836	$ 705	$ 595
Tax refunds, net	(34)	(85)	(135)
Common Stock
Non-cash financing and investing activities:
Dividends declared but not paid	251	231	200
Preferred and Preference Stock
Non-cash financing and investing activities:
Dividends declared but not paid	11	12	12
SCE
Cash payments (receipts):
Interest, net of amounts capitalized	713	615	552
Tax refunds, net	(50)	(164)	(57)
Non-cash financing and investing activities:
Accrued capital expenditures	730	643	594
SCE | Common Stock
Non-cash financing and investing activities:
Dividends declared but not paid	0	200	0
SCE | Preferred and Preference Stock
Non-cash financing and investing activities:
Dividends declared but not paid	$ 11	$ 12	$ 12