Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Changes in Accumulated Other Comprehensive Loss
Total equity	$ 4,621	$ 6,073	$ 9,558
Other comprehensive income (loss), net of tax	12	(6)	15
Total equity	3,426	4,621	$ 6,073
Total
Changes in Accumulated Other Comprehensive Loss
Total equity	(61)
Other comprehensive income before reclassifications, net of tax	12
Other comprehensive income (loss), net of tax	12
Total equity	(49)	(61)
Translation Adjustments, Net of Tax
Changes in Accumulated Other Comprehensive Loss
Total equity	(40)
Other comprehensive income before reclassifications, net of tax	9
Other comprehensive income (loss), net of tax	9
Total equity	(31)	(40)
Post-Retirement Benefits, Net of Tax
Changes in Accumulated Other Comprehensive Loss
Total equity	(21)
Other comprehensive income before reclassifications, net of tax	3
Other comprehensive income (loss), net of tax	3
Total equity	$ (18)	$ (21)