Debt Instrument, Covenant, Lien Threshold, Amount

No definition available.

Name:	iff_DebtInstrumentCovenantLienThresholdAmount
Namespace Prefix:	iff_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Covenant, Lien Threshold, Percentage Of Consolidated Net Tangible Assets

+ References

No definition available.

+ Details

Name:	iff_DebtInstrumentCovenantLienThresholdPercentageOfConsolidatedNetTangibleAssets
Namespace Prefix:	iff_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Covenant, Maximum Consolidated Leverage Ratio

+ References

No definition available.

+ Details

Name:	iff_DebtInstrumentCovenantMaximumConsolidatedLeverageRatio
Namespace Prefix:	iff_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- 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

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from borrowing by issuing commercial paper.

+ References

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommercialPaper
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Name:	us-gaap_ProceedsFromLinesOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow due to repaying amounts borrowed by issuing commercial paper.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfCommercialPaper
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=iff_TermLoanCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=iff_EuroInterbankOfferedRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=iff_SeniorNotesDueTwoThousandTwentyThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_FiscalQuarterEndingOnOrBeforeJune302023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_FiscalQuarterEndingSeptember302023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_SubsequentFiscalQuarterEndingOnOrBeforeMarch312024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_FiscalQuarterEndingJune302024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_FiscalQuarterEndingSeptember302024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	iff_DebtCovenantPeriodAxis=iff_FiscalQuarterEndingDecember312024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt - Narrative (Details) - USD ($) $ in Millions			3 Months Ended
Debt - Narrative (Details) - USD ($) $ in Millions	May 01, 2023	Mar. 31, 2023	Mar. 31, 2023	Mar. 31, 2022	Mar. 23, 2023
Debt Instrument [Line Items]
Proceeds from issuance of commercial paper (maturities after three months)			$ 1,320	$ 873
Repayments of commercial paper			$ 919	$ 566
Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, amount					$ 400
Term loan covenant, lien threshold, percentage of consolidated net tangible assets					5.00%
Term loan credit agreement \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Adjustment on variable rate, percent		0.10%
Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, amount					$ 400
Term loan covenant, lien threshold, percentage of consolidated net tangible assets					5.00%
Revolving credit facility \| Subsequent Event \| Loans payable
Debt Instrument [Line Items]
Proceeds from lines of credit	$ 400
Revolving credit facility \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Adjustment on variable rate, percent		0.10%
Revolving credit facility \| Euro Interbank Offered Rate
Debt Instrument [Line Items]
Adjustment on variable rate, percent		0.10%
2023 Notes \| Subsequent Event \| Loans payable
Debt Instrument [Line Items]
Repayments of debt	$ 300
Fiscal Quarter Ending On Or Before June 30, 2023 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					525.00%
Fiscal Quarter Ending On Or Before June 30, 2023 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					525.00%
Fiscal Quarter Ending September 30, 2023 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					500.00%
Fiscal Quarter Ending September 30, 2023 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					500.00%
Subsequent Fiscal Quarter Ending On Or Before March 31, 2024 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					475.00%
Subsequent Fiscal Quarter Ending On Or Before March 31, 2024 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					475.00%
Fiscal Quarter Ending June 30, 2024 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					450.00%
Fiscal Quarter Ending June 30, 2024 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					450.00%
Fiscal Quarter Ending September 30, 2024 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					425.00%
Fiscal Quarter Ending September 30, 2024 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					425.00%
Fiscal Quarter Ending December 31, 2024 \| Term loan credit agreement
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					400.00%
Fiscal Quarter Ending December 31, 2024 \| Revolving credit facility
Debt Instrument [Line Items]
Term loan covenant, maximum consolidated leverage ratio					400.00%