Commitments and Contingencies (Schedule of Estimated Losses) (Details) - 2017/2018 Wildfire/Mudslide Event - USD ($) $ in Millions	3 Months Ended			9 Months Ended		31 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020
Loss Contingency Accrual [Roll Forward]
Loss estimate balance at December 31, 2019	$ 4,500	$ 5,801		$ 4,541
Increase in accrued estimated losses to reflect best estimate	1,297		$ 0	1,297	$ 0
Amounts paid				(37)
Fixed payments to be made under settlement agreements				(1,192)
Loss estimate balance	4,609			4,609
Fixed payments to be made under executed settlement agreements3	1,192			1,192
Estimated total liabilities at September 30, 2020	4,600	4,541	5,801	4,600	5,801	$ 4,500
Charge for wildfire-related claims	1,297		0	1,297	0
Expected insurance recoveries	0		0	0	0
Expected revenue from FERC customers	(84)		0	(84)	0
Total pre-tax charge	1,213		0	1,213	0
Income tax benefit	(339)		0	(339)	0
Total after-tax charge	874		0	874	0
Southern California Edison
Loss Contingency Accrual [Roll Forward]
Loss estimate balance at December 31, 2019	4,500	5,801		4,541
Increase in accrued estimated losses to reflect best estimate	1,297		0	1,297	0	6,200
Amounts paid		(360)		(37)
Fixed payments to be made under settlement agreements				(1,192)		(1,600)
Loss estimate balance	4,609			4,609
Fixed payments to be made under executed settlement agreements3	1,192			1,192
Estimated total liabilities at September 30, 2020	4,600	$ 4,541	5,801	4,600	5,801	4,500
Charge for wildfire-related claims	1,297		0	1,297	0	$ 6,200
Expected insurance recoveries	0		0	0	0
Expected revenue from FERC customers	(84)		0	(84)	0
Total pre-tax charge	1,213		0	1,213	0
Income tax benefit	(339)		0	(339)	0
Total after-tax charge	$ 874		$ 0	$ 874	$ 0