Leases (Summary of Lease Payments) (Details) - SCE $ in Millions	3 Months Ended
	Jun. 30, 2019 USD ($) contract	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Operating Leases
Lease liabilities		$ 689
Finance Leases
2020		1
2021		1
2022		1
2023		2
2024		2
Thereafter		8
Total lease payments		15
Amount representing interest		6
Lease liabilities		9
Capital Leases
2019			$ 5
2020			6
2021			6
2022			6
2023			5
Thereafter			66
Total future commitments			94
Amount representing executory costs			25
Amount representing interest			33
Net commitments			36
Number of power contracts amended | contract	3
Reduction in ROU assets	$ 161
PPA Operating Leases
Operating Leases
2020		70
2021		48
2022		48
2023		47
2024		47
Thereafter		489
Total lease payments		749
Amount representing interest		220
Lease liabilities		529
Operating Leases
2019			148
2020			124
2021			103
2022			79
2023			47
Thereafter			536
Total lease payments			1,037
Other Operating Leases
Operating Leases
2020		37
2021		30
2022		24
2023		19
2024		14
Thereafter		95
Total lease payments		219
Amount representing interest		59
Lease liabilities		$ 160
Operating Leases
2019			42
2020			31
2021			27
2022			22
2023			17
Thereafter			101
Total lease payments			$ 240