Credit Facilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 750
Maximum borrowing capacity	$ 850
Debt Instrument, Covenant Description	65.00%
Ratio of Indebtedness to Net Capital	0.551
Commercial Paper, Maximum Term	270 days
Short-term Debt	$ 0	$ 146
Line of Credit Facility, Amount Outstanding	0
letter of credit facility	320
Letters of Credit Outstanding, Amount	85	$ 40
FERC Authorized Short-term Debt, effective through February 6, 2014	$ 900