Commitments and Contingencies (Current Wildfire Insurance Coverage) (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended	12 Months Ended				13 Months Ended
	Jul. 31, 2019	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 30, 2018	Jun. 30, 2020
Loss Contingencies [Line Items]
Wildfire insurance expense					$ 400
Forecast
Loss Contingencies [Line Items]
Wildfire insurance expense				$ 450
Southern California Edison
Loss Contingencies [Line Items]
Wildfire-specific insurance coverage						$ 1,000	$ 1,200
Co-Insurance per wildfire occurrence							115
Self-insured retention		$ 10					50
Wildfire-specific insurance coverage, net							$ 1,000
Southern California Edison | CPUC
Loss Contingencies [Line Items]
Requested rate increase	$ 478
Authorized recovery	$ 505
Southern California Edison | Forecast
Loss Contingencies [Line Items]
Wildfire-specific insurance coverage			$ 1,000
Co-Insurance per wildfire occurrence			80
Self-insured retention			50
Wildfire-specific insurance coverage, net			$ 870