Commitments and Contingencies (Southern California Wildfires and Mudslides) (Details) a in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
	Jul. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Nov. 30, 2018 USD ($) a structure fatality	Oct. 29, 2019 a structure fatality	Jan. 31, 2019 claim	Sep. 30, 2018 claim	Jan. 01, 2018 structure fatality	Dec. 31, 2017 a structure fatality
Loss Contingencies [Line Items]
Estimated losses		$ 4,669,000,000	$ 4,669,000,000
2017/2018 Wildfire/Mudslide Event
Loss Contingencies [Line Items]
Derivative lawsuits | claim							2
San Onofre OII
Loss Contingencies [Line Items]
Derivative lawsuits | claim						2
2017/2018 Wildfire/Mudslide Event
Loss Contingencies [Line Items]
Estimated losses		$ 4,700,000,000	4,700,000,000
Estimated losses after tax			1,800,000,000
Southern California Edison
Loss Contingencies [Line Items]
High fire risk service area, percent		27.00%
Estimated losses		$ 4,669,000,000	4,669,000,000
Wildfire-specific insurance coverage			1,000,000,000	$ 300,000,000
Self-insured retention			10,000,000
Other general liability insurance coverage			450,000,000
Southern California Edison | CPUC
Loss Contingencies [Line Items]
Requested rate increase	$ 478,000,000
Southern California Edison | Thomas and Koenigstein Fires
Loss Contingencies [Line Items]
Acres burned | a									280
Structures destroyed | structure									1,343
Fatalities | fatality									2
Southern California Edison | Thomas and Koenigstein Fires | CPUC
Loss Contingencies [Line Items]
Requested rate increase	$ 5,900,000
Southern California Edison | Woolsey Fire
Loss Contingencies [Line Items]
Acres burned | a				100
Structures destroyed | structure				1,643
Fatalities | fatality				3
Structures damaged | structure				364
Additional fatalities | fatality				2
Wildfire-specific insurance coverage			1,000,000,000
Self-insured retention			10,000,000
Southern California Edison | Montecito Mudslides
Loss Contingencies [Line Items]
Structures destroyed | structure								135
Fatalities | fatality								21
Structures damaged | structure								324
Additional presumed fatalities | fatality								2
Southern California Edison | 2017/2018 Wildfire/Mudslide Event
Loss Contingencies [Line Items]
Estimated losses		4,700,000,000	4,700,000,000
Expected insurance recoveries		2,000,000,000.0	2,000,000,000.0
Expected revenue from FERC customers		135,000,000	135,000,000
Total after-tax charge			1,800,000,000
Estimated losses after tax		$ 1,800,000,000	$ 1,800,000,000
Subsequent event | Southern California Edison | Saddle Ridge Fire
Loss Contingencies [Line Items]
Acres burned | a					9
Structures destroyed | structure					19
Fatalities | fatality					1
Structures damaged | structure					88