Derivative Instruments (Notional Values) (Details) - SCE - Electric Utility - Gross amounts recognized	12 Months Ended
	Dec. 31, 2020 GWh Bcfe	Dec. 31, 2019 GWh Bcfe
Electricity options, swaps and forwards (GWh)
Derivatives
Notional volumes of derivative instruments	1,581	3,155
Natural gas options, swaps and forwards (Bcf)
Derivatives
Notional volumes of derivative instruments | Bcfe	34	43
Congestion revenue rights (GWh)
Derivatives
Notional volumes of derivative instruments	41,151	48,170