Restructuring and Other Charges, Net - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 3
Ending Balance	17
Additional charges, net	17	$ 3
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance	3
Additional Charges (Reversals), Net	17
Non-Cash Charges	0
Payments	(3)
Ending Balance	17
IFF Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	3
Additional Charges (Reversals), Net	17
Non-Cash Charges	0
Payments	(3)
Ending Balance	17
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	2	1
Food Ingredients
Restructuring Reserve [Roll Forward]
Additional charges, net	3	1
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	3	1
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 9	$ 0

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.

+ References

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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.

+ References

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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