Commitments and Contingencies (Contingencies) (Details) a in Thousands	12 Months Ended	13 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	May 31, 2019 USD ($)	Jan. 31, 2019 claims	Nov. 30, 2018 a structure fatality	Sep. 30, 2018 claims	Jan. 01, 2018 structure fatality	Dec. 31, 2017 USD ($) a structure fatality
Loss Contingencies [Line Items]
Charge for wildfire-related claims	$ 4,669,000,000	$ 4,669,000,000						$ 0
SCE
Loss Contingencies [Line Items]
High fire risk service area, percent	35.00%
Charge for wildfire-related claims	$ 4,669,000,000	4,669,000,000						$ 0
Wildfire insurance coverage	1,000,000,000	300,000,000
Self insurance	10,000,000	10,000,000	$ 10,000,000
Other general liability insurance coverage	450,000,000	450,000,000
SCE | December 2017 Wildfires
Loss Contingencies [Line Items]
Acres burned | a								280
Structures destroyed | structure								1,063
Structures damaged | structure								280
Fatalities | fatality								2
SCE | Montecito Mudslides
Loss Contingencies [Line Items]
Structures destroyed | structure							135
Structures damaged | structure							324
Fatalities | fatality							21
Additional fatalities presumed | fatality							2
SCE | November 2018 Wildfires
Loss Contingencies [Line Items]
Acres burned | a					100
Structures destroyed | structure					1,643
Structures damaged | structure					364
Fatalities | fatality					3
Capital expenditures related to restoration of service	82,000,000	82,000,000
Wildfire insurance coverage	1,000,000,000
Self insurance	10,000,000	10,000,000
SCE | December 2017 Wildfires and Montecito Mudslides
Loss Contingencies [Line Items]
Capital expenditures related to restoration of service	89,000,000	89,000,000
SCE | 2017/2018 Wildfire/Mudslide Events
Loss Contingencies [Line Items]
Charge for wildfire-related claims	4,669,000,000	4,669,000,000
Expected insurance recoveries	(2,000,000,000)	(2,000,000,000)
Expected revenue from FERC customers	135,000,000	$ 135,000,000
Total after-tax charge	$ 1,825,000,000
December 2017 Wildfires and Montecito Mudslides
Loss Contingencies [Line Items]
Lawsuits | claims						2
San Onofre OII | Subsequent event
Loss Contingencies [Line Items]
Lawsuits | claims				2