Supplemental Cash Flows Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash payments for interest and taxes:
Interest, net of amounts capitalized	$ 254	$ 240
Tax refunds, net	(93)
Tax payments, net		14
Common stock
Dividends declared but not paid:
Dividends declared but not paid	197	177
Preferred and preference stock
Dividends declared but not paid:
Dividends declared but not paid	12	12
Southern California Edison
Cash payments for interest and taxes:
Interest, net of amounts capitalized	233	223
Tax refunds, net	(18)
Tax payments, net		20
Dividends declared but not paid:
Accrued capital expenditures	412	283
Southern California Edison | Common stock
Dividends declared but not paid:
Dividends declared but not paid	100	0
Southern California Edison | Preferred and preference stock
Dividends declared but not paid:
Dividends declared but not paid	$ 12	$ 12