Commitments and Contingencies (Other Lease Commitments) (Details) - SCE - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Leased Assets [Line Items]
Operating leases expense	$ 57	$ 59	$ 68
Total
Operating Leased Assets [Line Items]
2019	42
2020	31
2021	27
2022	22
2023	17
Thereafter	101
Total future commitments	$ 240