Investments (Nuclear Decommissioning Trusts) (Details) - Southern California Edison - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Investment Holdings [Line Items]
Unrealized holding gains, net of losses	$ 1,700	$ 1,400
Other-than-temporary impairments	160	170
Deferred income taxes related to unrealized gains	383	323
Nuclear decommissioning trusts	$ 4,000	$ 3,800