Commitments and Contingencies (Wildfire loss expense) (Details) - 2017/2018 Wildfire/Mudslide Events - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Charge for wildfire-related claims	$ 1,265	$ 1,297
Expected revenue from FERC customers	(67)	(84)
Total pre-tax charge	1,198	1,213
Income tax benefit	(304)	(339)
Total after-tax charge	894	$ 874
SCE
Loss Contingencies [Line Items]
Expected insurance recoveries	$ (708)