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Restructuring and Other Charges - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 3
Ending Balance	$ 33		33
Additional charges, net	16	$ 1	54	$ 6
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance			3
Additional Charges (Reversals), Net			54
Payments			(24)
Ending Balance	33		33
IFF Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			3
Additional Charges (Reversals), Net	16		54
Payments			(24)
Ending Balance	33		33
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	9	0	17	1
Food Ingredients
Restructuring Reserve [Roll Forward]
Additional charges, net	2	0	12	2
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	4	0	12	1
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 1	$ 0	$ 13	$ 1