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Restructuring and Other Charges - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		21 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 34
Ending Balance	$ 16		16		$ 16
Additional charges, net	6	$ 20	10	$ 35
IFF Productivity Program
Restructuring Reserve [Roll Forward]
Beginning Balance			34
Additional Charges (Reversals), Net			10
Non-Cash Charges			(1)
Payments			(27)
Ending Balance	16		16		16
IFF Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			34
Additional Charges (Reversals), Net			10		78
Non-Cash Charges			(1)
Payments			(27)
Ending Balance	16		16		$ 16
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	3	8	5	10
Health & Biosciences
Restructuring Reserve [Roll Forward]
Additional charges, net	3	7	5	11
Scent
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 0	$ 5	$ 0	$ 14