NOTES RECEIVABLE FROM PARTICIPANTS (Details) - EBP 001	12 Months Ended
Dec. 31, 2025 USD ($) loan	Dec. 31, 2024
EBP, Contribution [Line Items]
Note receivable from participant, maximum borrowing to total account, percent	50.00%
Note receivable from participant, maximum borrowing amount	$ 50,000
Note receivable from participant, loan look back period	12 months
Note receivable from participant, minimum borrowing, amount	$ 1,000
Note receivable from participant, maximum number of outstanding participant loans \| loan	2
Note receivable from participant, collateralized percentage of vested account balance	0.50
Note receivable from participant, loan setup fee	$ 75
Note receivable from participant, loan annual maintenance fee	$ 25
Minimum
EBP, Contribution [Line Items]
Participant loan, interest rate	3.75%	3.75%
Maximum
EBP, Contribution [Line Items]
Participant loan, interest rate	9.00%	9.00%

EBP, Note Receivable From Participant, Account, Participant Loan Annual Maintenance Fee

No definition available.

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Balance Type:	debit
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- Definition

EBP, Note Receivable From Participant, Account, Participant Loan Look Back Period

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Account, Participant Loan Setup Fee

+ References

No definition available.

+ Details

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Namespace Prefix:	iff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

EBP, Note Receivable From Participant, Collateralized Percentage Of Vested Account Balance

+ References

No definition available.

+ Details

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Namespace Prefix:	iff_
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Balance Type:	na
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, Maximum Number Of Outstanding Participant Loans

+ References

No definition available.

+ Details

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Namespace Prefix:	iff_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(4)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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- Details

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