Commitments and Contingencies (Wildfire Insurance Coverage) (Details) - USD ($) $ in Millions		1 Months Ended				6 Months Ended	12 Months Ended
	Jul. 01, 2021	Jul. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jul. 31, 2019	Jun. 30, 2021	Dec. 31, 2020
SCE
Loss Contingencies [Line Items]
Requested increase (decrease) in revenue requirement			$ 214		$ 505
Wildfire insurance coverage						$ 1,000
Co-insurance						75
Self insurance						50
Coverage net						875
Approved regulatory increase (decrease) in revenue				$ 505
Regulatory assets			8,434			9,605	$ 8,434
Revenue recovery period					2 years
SCE | Forecast
Loss Contingencies [Line Items]
Wildfire insurance expense	$ 425
SCE | Wildfire insurance costs
Loss Contingencies [Line Items]
Requested increase (decrease) in revenue requirement			204		$ 478
Wildfire insurance expense		$ 460
2017/2018 Wildfire/Mudslide Events
Loss Contingencies [Line Items]
Expected revenue from FERC customers						94
2017/2018 Wildfire/Mudslide Events | SCE
Loss Contingencies [Line Items]
Expected insurance recoveries			$ 708				708
Insurance settlements and recoveries						708
Requested increase (decrease) in revenue requirement					$ 60
Potential impairment						189
Expected FERC cumulative recoveries						233
Expected revenue from FERC customers						94
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						4,800
Insurance settlements and recoveries						2,000
November 2018 - Woolsey Wildfires
Loss Contingencies [Line Items]
Litigation settlement							$ 2,212
November 2018 - Woolsey Wildfires | SCE
Loss Contingencies [Line Items]
Wildfire insurance coverage						1,000
Self insurance						$ 10