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Restructuring and Other Charges (Credits) - Activity and Reserve Balances for Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 4
Cash payments			(2)
Restructuring charges (credits)			(4)
Other			6
Restructuring reserve, ending balance	$ 4		4
Forged Wheels
Restructuring Cost and Reserve [Line Items]
Gain (loss) on sale of assets	2		2
UK \| Engineered Structures
Restructuring Cost and Reserve [Line Items]
Gain (loss) on sale of assets		$ (14)	3	$ (14)
Layoff costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			4
Cash payments			(1)
Restructuring charges (credits)			1
Other			0
Restructuring reserve, ending balance	4		4
Other exit costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			0
Cash payments			(1)
Restructuring charges (credits)			(5)
Other			6
Restructuring reserve, ending balance	$ 0		$ 0