Commitments and Contingencies (Schedule of Estimated Losses) (Details) - USD ($) $ in Millions		1 Months Ended			2 Months Ended	3 Months Ended	12 Months Ended		37 Months Ended
	Jan. 22, 2021	Jan. 31, 2021	Oct. 31, 2020	Sep. 30, 2020	Feb. 18, 2021	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Loss Contingency Accrual [Roll Forward]
Wildfire-related claims										$ 2,231	$ 0
Woolsey Fire
Loss Contingency Accrual [Roll Forward]
Beginning balance		$ 2,152			$ 2,152
Ending balance							$ 2,152		$ 2,152
Loss contingency accrual		2,152			2,152		2,152		2,152	2,152
Woolsey Fire | Subsequent event
Loss Contingency Accrual [Roll Forward]
Litigation settlement	$ 2,212
2017/2018 Wildfire/Mudslide Events
Loss Contingency Accrual [Roll Forward]
Beginning balance		4,400			4,400
Ending balance							4,400		4,400
Loss contingency accrual		4,400			4,400		4,400		4,400	4,400
2017/2018 Wildfire/Mudslide Events | Subsequent event
Loss Contingency Accrual [Roll Forward]
Litigation settlement	19
Other wildfire-related claims
Loss Contingency Accrual [Roll Forward]
Beginning balance		129			129
Ending balance							129		129
Loss contingency accrual		129			129		129		129	129
2017/2018 Wildfire/Mudslide Events
Loss Contingency Accrual [Roll Forward]
Beginning balance		4,400			4,400		4,500
Increase in accrued estimated losses to reflect best estimate				$ 1,300
Ending balance						$ 4,500	4,400	$ 4,500	4,400
Loss contingency accrual		4,400			4,400	4,500	4,500	4,500	4,400	4,400	4,500
Loss Contingency Accrual, Disclosures [Abstract]
Charge for wildfire-related claims				1,300
2017/2018 Wildfire/Mudslide Events | Deferred credits and other liabilities
Loss Contingency Accrual [Roll Forward]
Beginning balance		2,281			2,281
Ending balance							2,281		2,281
Loss contingency accrual		2,281			2,281		2,281		2,281	2,281
SCE
Loss Contingency Accrual [Roll Forward]
Wildfire-related claims										2,231	0
SCE | Woolsey Fire
Loss Contingency Accrual [Roll Forward]
Beginning balance		2,152			2,152
Ending balance							2,152		2,152
Loss contingency accrual		2,152			2,152		2,152		2,152	2,152
SCE | Woolsey Fire | Subsequent event
Loss Contingency Accrual [Roll Forward]
Litigation settlement	2,212
SCE | 2017/2018 Wildfire/Mudslide Events
Loss Contingency Accrual [Roll Forward]
Beginning balance		4,400			4,400
Ending balance							4,400		4,400
Loss contingency accrual		4,400			4,400		4,400		4,400	4,400
SCE | 2017/2018 Wildfire/Mudslide Events | Subsequent event
Loss Contingency Accrual [Roll Forward]
Litigation settlement	$ 19
SCE | Other wildfire-related claims
Loss Contingency Accrual [Roll Forward]
Beginning balance		129			129
Ending balance							129		129
Loss contingency accrual		129			129		129		129	129
SCE | 2017/2018 Wildfire/Mudslide Events
Loss Contingency Accrual [Roll Forward]
Beginning balance		4,383			4,383		4,541
Increase in accrued estimated losses to reflect best estimate				1,300			1,297	232	6,200
Amounts paid			$ (1,200)			(360)	(1,455)
Ending balance						4,541	4,383	4,541	4,383
Litigation settlement							300
Loss contingency accrual		4,383			4,383	$ 4,541	4,383	4,541	4,383	4,383	$ 4,541
Loss Contingency Accrual, Disclosures [Abstract]
Charge for wildfire-related claims				$ 1,300			1,297	232	6,200
Expected revenue from FERC customers							(84)	(14)
Total pre-tax charge							1,213	218
Income tax benefit							(339)	(61)
Total after-tax charge							874	$ 157
SCE | 2017/2018 Wildfire/Mudslide Events | Deferred credits and other liabilities
Loss Contingency Accrual [Roll Forward]
Beginning balance		2,281			2,281
Ending balance							2,281		2,281
Loss contingency accrual		2,281			2,281		$ 2,281		$ 2,281	$ 2,281
SCE | 2017/2018 Wildfire/Mudslide Events | Subsequent event
Loss Contingency Accrual [Roll Forward]
Amounts paid		$ (2,200)
Litigation settlement					$ 80