Transition Activities - Schedule of Retention Benefit Liability Roll Forward (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Restructuring Reserve [Roll Forward]
Other current liabilities	$ 163		$ 163		$ 166
Retention Benefits
Restructuring Reserve [Roll Forward]
Retention benefit liability at beginning of period			21	$ 14
Costs deferred as a regulatory asset	4	$ 11	14	14
Costs paid or settled			(13)	0
Retention benefit liability at the end of the period	22	28	22	28
Other current liabilities	$ 11	$ 25	$ 11	$ 25