Restructuring and Other Charges, Net - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 36
Ending Balance	23
Additional charges, net	6	$ 17
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance	36
Additional Charges (Reversals), Net	6
Non-Cash Charges	(1)
Cash Payments	(18)
Ending Balance	23
IFF Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	36
Cash Payments	(18)
Ending Balance	23
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	2	2
Food Ingredients
Restructuring Reserve [Roll Forward]
Additional charges, net	2	3
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	2	3
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 0	$ 9

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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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