Restructuring and Other Credits - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Restructuring Cost and Reserve [Line Items]
Restructuring and other credits	$ (93)	$ (4)
Reversal of previously recorded layoff reserve	0	1
Engineered Structures \| UK
Restructuring Cost and Reserve [Line Items]
Gain from sale of assets		$ 3
Disposed by Sale \| Disk Forging Facility
Restructuring Cost and Reserve [Line Items]
Gain from disposal of business	$ 93

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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