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Restructuring and Other Charges - Narrative (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 Cost and Reserve [Line Items]
Restructuring and other charges	$ 6	$ 20	$ 10	$ 35
IFF Productivity Program
Restructuring Cost and Reserve [Line Items]
Additional Charges (Reversals), Net			10
IFF Productivity Program \| Minimum \| Taste, Food Ingredients, Health And Biosciences, And Scent
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	85		85		$ 85
IFF Productivity Program \| Maximum \| Taste, Food Ingredients, Health And Biosciences, And Scent
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	100		100		100
Employee Severance \| IFF Productivity Program
Restructuring Cost and Reserve [Line Items]
Additional Charges (Reversals), Net			10		78
Restructuring Costs	$ 20		$ 35
Fixed Asset Write Down [Member] \| IFF Productivity Program
Restructuring Cost and Reserve [Line Items]
Restructuring Costs					$ 1