Derivative Instruments (Notional Values) (Details) - Southern California Edison - Electric Utility - Economic Hedges	3 Months Ended	12 Months Ended
	Mar. 31, 2019 Bcfe GWh	Dec. 31, 2018 Bcfe GWh
Electricity options, swaps and forwards (GWh)
Derivative [Line Items]
Notional volumes of derivative instruments	2,515	2,786
Natural gas options, swaps and forwards (Bcf)
Derivative [Line Items]
Notional volumes of derivative instruments | Bcfe	4	20
Congestion revenue rights (GWh)
Derivative [Line Items]
Notional volumes of derivative instruments	39,401	54,453