Commercial Paper (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Amount outstanding at period end	$ 47	$ 47	$ 83
money pool
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	150	150	150
Amount outstanding at period end	0	0	0
Average amount outstanding	1	25	16
Maximum amount outstanding	$ 16	$ 81	$ 78
Line of Credit Facility, Interest Rate During Period	4.07%	1.10%	0.05%
Commercial Paper [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 150	$ 150	$ 150	$ 150
Amount outstanding at period end	47	47	83	19
Average amount outstanding	9	18	3	30
Maximum amount outstanding	$ 52	$ 123	$ 83	$ 95
Line of Credit Facility, Interest Rate During Period	4.39%	1.03%	0.18%	1.59%
Weighted average interest rate at period end (percentage)	4.55%	4.55%	0.21%	0.17%