Restructuring - Schedule of Changes in Balance Sheet Position of Employee Related Restructuring Reserves (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Restructuring Cost and Reserve [Line Items]
Provision - charge	$ 0		$ 0
Restructuring employee-related
Restructuring Cost and Reserve [Line Items]
Reserve at beginning of the period	117	$ 189	151	$ 213
Provision - charge	2	9	4	22
Provision - reversal	0	(1)	(0)	(1)
Cash payments	(17)	(19)	(67)	(49)
Translation difference	0	8	14	1
Reserve at end of the period	$ 101	$ 187	$ 101	$ 187

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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