Financial Instruments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Sep. 30, 2010 Swap
Derivatives, Fair Value [Line Items]
Number of interest rate swap agreements		2
Loss incurred on termination of interest rate swaps	$ (2.7)
Derivative losses included in AOCI	$ 4.3
Cross currency swap [Member]
Derivatives, Fair Value [Line Items]
Derivative instrument maturity period (years)	10 years
Forward currency contracts [Member]
Derivatives, Fair Value [Line Items]
Number of multiple forward currency contracts matured	2

Deferred Gain Loss On Terminated Interest Rate Contracts

No definition available.

Name:	iff_DeferredGainLossOnTerminatedInterestRateContracts
Namespace Prefix:	iff_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of forward currency contracts that matured during the period.

+ References

No definition available.

+ Details

Name:	iff_NumberOfForwardCurrencyContractsThatMaturedDuringPeriod
Namespace Prefix:	iff_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of interest rate swaps entered into during the period.

+ References

No definition available.

+ Details

Name:	iff_NumberOfInterestRateSwapAgreements
Namespace Prefix:	iff_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration