Stockholders' Equity - Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at Beginning of Year	$ 14,306	$ 12,781	$ 12,733
Net Income	53	80
Reclassification Adjustments	(1)	(22)
Balance at End of Year	15,547	14,306	12,781
Pensions and other postretirement liabilities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at Beginning of Year	(240)	(292)
Net Income	49	74
Reclassification Adjustments	(1)	(22)
Balance at End of Year	(192)	(240)	(292)
Other comprehensive income of equity investees
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at Beginning of Year	(22)	(28)
Net Income	4	6
Reclassification Adjustments	0	0
Balance at End of Year	(18)	(22)	(28)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at Beginning of Year	(262)	(320)	(351)
Balance at End of Year	$ (210)	$ (262)	$ (320)