Commitments and Contingencies (Wildfire Insurance Coverage) (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jul. 31, 2019	Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Wildfire insurance expense						$ 450
SCE
Loss Contingencies [Line Items]
Requested increase (decrease) in revenue requirement	$ 214		$ 505
Wildfire insurance coverage					$ 1,000
Co-insurance					80
Self insurance					50
Coverage net					$ 870
Approved regulatory increase (decrease) in revenue		$ 505
Regulatory assets	8,434			$ 9,121		8,434
Revenue recovery period			2 years
SCE | Wildfire insurance costs
Loss Contingencies [Line Items]
Requested increase (decrease) in revenue requirement	204		$ 478
2017/2018 Wildfire/Mudslide Events
Loss Contingencies [Line Items]
Expected insurance recoveries				666
Expected revenue from FERC customers				91
2017/2018 Wildfire/Mudslide Events | SCE
Loss Contingencies [Line Items]
Expected insurance recoveries	$ 708			666		708
Insurance settlements and recoveries				42
Requested increase (decrease) in revenue requirement			$ 6
Expected FERC cumulative recoveries				233
Expected revenue from FERC customers				91
Wildfire insurance coverage				1,000
Self insurance				10
2017/2018 Wildfire/Mudslide Events | SCE | Aggregate
Loss Contingencies [Line Items]
Increase in accrued estimated losses to reflect best estimate				6,200
Litigation settlement				4,200
Insurance settlements and recoveries				1,300
December 2017 - Thomas and Koenigstein Wildfires | SCE
Loss Contingencies [Line Items]
Expected insurance recoveries				0
November 2018 - Woolsey Wildfires
Loss Contingencies [Line Items]
Litigation settlement						$ 2,212
November 2018 - Woolsey Wildfires | SCE
Loss Contingencies [Line Items]
Expected insurance recoveries				666
Wildfire insurance coverage				1,000
Self insurance				$ 10