Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Deferred tax liabilities:
Property, plant and equipment	$ (1,524,000,000)	$ (1,464,000,000)
Intangible assets	(83,000,000)	(95,000,000)
Other	(40,000,000)	(50,000,000)
Total deferred tax liabilities	(1,647,000,000)	(1,609,000,000)
Deferred tax assets:
Payable to affiliate due to post-retirement benefit plan participation	312,000,000	292,000,000
Other	1,000,000	0
Gross deferred tax assets	313,000,000	292,000,000
Less valuation allowance on deferred tax assets	0	0
Net deferred tax assets	313,000,000	292,000,000
Net deferred tax liabilities	$ (1,334,000,000)	$ (1,317,000,000)