Leases (Summary of Lease Payments) (Details) - Southern California Edison $ in Millions	3 Months Ended
	Jun. 30, 2019 USD ($) contract	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Operating Leases
Lease liabilities		$ 701
Finance Leases
2019		0
2020		1
2021		1
2022		2
2023		2
Thereafter		9
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 lease payments			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
Reduction in lease liabilities	$ 161
PPA Operating Leases
Operating Leases
2019		20
2020		70
2021		48
2022		48
2023		47
Thereafter		536
Total lease payments		769
Amount representing interest4		226
Lease liabilities		543
Operating Leases
2019			148
2020			124
2021			103
2022			79
2023			47
Thereafter			536
Total lease payments			1,037
Other Operating Leases
Operating Leases
2019		11
2020		35
2021		28
2022		23
2023		17
Thereafter		104
Total lease payments		218
Amount representing interest4		60
Lease liabilities		$ 158
Operating Leases
2019			42
2020			31
2021			27
2022			22
2023			17
Thereafter			101
Total lease payments			$ 240