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Restructuring and Other (Credits) Charges - Activity and Reserve Balances for Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 4
Cash payments			(4)
Restructuring charges (credits)			(4)
Other			7
Restructuring reserve, ending balance	$ 3		3
Forged Wheels
Restructuring Cost and Reserve [Line Items]
Gain (loss) on sale of assets			2
UK \| Engineered Structures
Restructuring Cost and Reserve [Line Items]
Gain (loss) on sale of assets	1	$ 1	3	$ (13)
Layoff costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			4
Cash payments			(2)
Restructuring charges (credits)			1
Other			0
Restructuring reserve, ending balance	3		3
Other exit costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			0
Cash payments			(2)
Restructuring charges (credits)			(5)
Other			7
Restructuring reserve, ending balance	$ 0		$ 0