Commitments and Contingencies (Wildfire loss expense) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
2017/2018 Wildfire/Mudslide Events
Commitments and Contingencies
Charge for wildfire-related claims		$ 90	$ 416
Expected revenue from FERC customers		(6)	(26)
Total pre-tax charge		84	390
Income tax benefit		(23)	(109)
Total after-tax charge		61	281
Post-2018 Wildfires
Commitments and Contingencies
Charge for wildfire-related claims	$ 45	6	150
Expected insurance recoveries	(43)		(139)
Total pre-tax charge	2	6	11
Income tax benefit	(1)	(2)	(3)
Total after-tax charge	$ 1	$ 4	$ 8