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Restructuring and Other Charges - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		24 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 34
Ending Balance	$ 13		13		$ 13
Additional charges, net	5	$ 14	15	$ 49
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance			34
Additional Charges (Reversals), Net			15
Non-Cash Charges			(1)
Payments			(35)
Ending Balance	13		13		13
IFF Productivity Program \| Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			34
Additional Charges (Reversals), Net			14		81
Non-Cash Charges			(1)
Payments			(34)
Ending Balance	13		13		13
IFF Productivity Program \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance			0
Additional Charges (Reversals), Net			1
Non-Cash Charges			0
Payments			(1)
Ending Balance	0		0		$ 0
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	2	9	7	19
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	2	4	7	15
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 1	$ 1	$ 1	$ 15