Leases (Summary of Other Information) (Details) - Southern California Edison $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Other operating leases	$ 9
Weighted average remaining lease term (in years)	12 years 1 month 21 days
Weighted average discount rate	8.70%
PPA Operating Leases
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 30
Weighted average remaining lease term (in years)	12 years 10 months 6 days
Weighted average discount rate	4.24%
Other Operating Leases
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 11
Weighted average remaining lease term (in years)	12 years 6 months 15 days
Weighted average discount rate	3.85%