Regulatory Assets and Liabilities (Textual) (Details) - USD ($) $ in Millions	12 Months Ended	13 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Feb. 28, 2019	Dec. 31, 2017	Dec. 19, 2017
Regulatory Assets [Line Items]
Regulatory assets	$ 5,380	$ 5,380		$ 4,914
SCE
Regulatory Assets [Line Items]
Regulatory assets	$ 5,380	5,380		$ 4,914
Regulatory assets, energy derivatives, low range of contract expiration (in years)	2 years
Regulatory assets, energy derivatives, high range of contract expiration (in years)	5 years
Regulatory assets related to deferred income taxes, recovery period, low range (in years)	1 year
Regulatory assets related to deferred income taxes, recovery period, high range (in years)	60 years
Low end of the range of remaining original amortization (in years)	10 years
High end of the range of remaining original amortization (in years)	35 years
Wildfire insurance coverage	$ 1,000	$ 300
Unamortized investments, net of accumulated amortization | SCE
Regulatory Assets [Line Items]
Return rate earned on assets included in rate base (as a percent)	7.61%	7.61%		7.90%
Regulatory assets	$ 118	$ 118		$ 123
Unamortized investments, net of accumulated amortization | SCE | Legacy Meters
Regulatory Assets [Line Items]
Return rate earned on assets included in rate base (as a percent)				6.46%
San Onofre | SCE
Regulatory Assets [Line Items]
Regulatory assets	0	0		$ 72	$ 775
Revenue subject to refund | Catastrophic event memorandum account | SCE
Regulatory Assets [Line Items]
Net Regulatory Assets	144	144		102
Revenue subject to refund | Wildfire expense memorandum account | SCE
Regulatory Assets [Line Items]
Net Regulatory Assets	128	128		0
Revenue subject to refund | FERC Balancing Account | SCE
Regulatory Assets [Line Items]
Net Regulatory Assets	$ (180)	$ (180)		$ (205)
Subsequent event | SCE
Regulatory Assets [Line Items]
Net Regulatory Assets			$ 107
Subsequent event | Revenue subject to refund | Wildfire liability insurance recovery | SCE
Regulatory Assets [Line Items]
Net Regulatory Assets			$ 107