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Restructuring and Other Charges - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 3
Ending Balance	$ 28		28
Additional charges, net	21	$ 2	38	$ 5
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance			3
Additional Charges (Reversals), Net			38
Non-Cash Charges			0
Payments			(13)
Ending Balance	28		28
IFF Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			3
Additional Charges (Reversals), Net	21		38
Non-Cash Charges			0
Payments			(13)
Ending Balance	28		28
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	6	0	8	1
Food Ingredients
Restructuring Reserve [Roll Forward]
Additional charges, net	7	1	10	2
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	5	0	8	1
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 3	$ 1	$ 12	$ 1