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Restructuring and Other Charges - Additional Information (Details)	3 Months Ended	12 Months Ended			25 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) Position	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2024 USD ($) position
Nutrition And Biosciences Restructuring Liability
Restructuring Cost and Reserve [Line Items]
Restructuring related settlement and impairment		$ 2,000,000	$ 2,000,000
Nutrition And Biosciences Restructuring Liability \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred		0	0
Nutrition & Biosciences, Inc
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred to date	$ 49,000,000	$ 49,000,000			$ 49,000,000
Nutrition & Biosciences, Inc \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred				$ 15,000,000
Number of positions eliminated \| Position		215
2023 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred		$ 4,000,000
Number of positions eliminated \| position					670
2023 Restructuring Program \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred			$ 70,000,000
IFF Productivity Program \| Maximum \| Nourish, Health And Biosciences, And Scent
Restructuring Cost and Reserve [Line Items]
Restructuring, expected cost	70,000,000	70,000,000			$ 70,000,000
IFF Productivity Program \| Minimum \| Nourish, Health And Biosciences, And Scent
Restructuring Cost and Reserve [Line Items]
Restructuring, expected cost	50,000,000	$ 50,000,000			$ 50,000,000
IFF Productivity Program \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring costs	3,000,000
IFF Productivity Program \| Fixed asset write down
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 20,000,000