Supplemental Cash Flows Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash payments (receipts):
Interest, net of amounts capitalized	$ 263	$ 233
Income taxes, net	(87)
Common Stock
Non-cash financing and investing activities:
Dividends declared but not paid	251	232
SCE
Cash payments (receipts):
Interest, net of amounts capitalized	241	210
Income taxes, net	(87)
Non-cash financing and investing activities:
Accrued capital expenditures	503	451
SCE | Common Stock
Non-cash financing and investing activities:
Dividends declared but not paid	$ 0	$ 0