Commitments and Contingencies (Wildfires and Mudslides) (Details) $ in Millions	1 Months Ended		6 Months Ended
	Sep. 30, 2020 USD ($) a item individual	Oct. 31, 2019 a individual item	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Nov. 30, 2018 a individual item	Jan. 31, 2018 individual item	Dec. 04, 2017 a item individual
2019/2020 Wildfires
Loss Contingencies [Line Items]
Charge for wildfire-related claims | $			$ 118
Expected insurance recoveries | $			75
2017/2018 Wildfire/Mudslide Events
Loss Contingencies [Line Items]
Expected revenue from FERC customers | $			94
Charge for wildfire-related claims | $			1,531	$ 4,383
Aggregate settlement payments | $			$ 4,700
SCE
Loss Contingencies [Line Items]
High fire risk service area, percent			27.00%
SCE | Saddle Ridge Fire
Loss Contingencies [Line Items]
Acres burned | a		9,000
Structures destroyed		19
Structures damaged		88
Fatalities | individual		1
Number of injured firefighters | individual		8
SCE | Bobcat fire
Loss Contingencies [Line Items]
Acres burned | a	116,000
Number of injured firefighters | individual	6
Estimated fire suppression costs | $	$ 80
SCE | Bobcat fire | Homes
Loss Contingencies [Line Items]
Structures destroyed	87
Structures damaged	28
SCE | Bobcat fire | Commercial property
Loss Contingencies [Line Items]
Structures destroyed	1
SCE | Bobcat fire | Minor structures
Loss Contingencies [Line Items]
Structures destroyed	83
Structures damaged	19
SCE | 2017/2018 Wildfire/Mudslide Events
Loss Contingencies [Line Items]
Expected revenue from FERC customers | $			$ 94
Expected insurance recoveries | $				$ 708
SCE | December 2017 - Thomas and Koenigstein Wildfires
Loss Contingencies [Line Items]
Acres burned | a							280,000
Structures destroyed							1,343
Fatalities | individual							2
SCE | November 2018 - Woolsey Wildfires
Loss Contingencies [Line Items]
Acres burned | a					100,000
Structures destroyed					1,643
Structures damaged					364
Fatalities | individual					3
Additional fatalities | individual					2
SCE | Montecito Mudslides
Loss Contingencies [Line Items]
Structures destroyed						135
Structures damaged						324
Fatalities | individual						21
Additional fatalities presumed | individual						2