Segment Information - Reportable Segment Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net sales	$ 3,088,533,000us-gaap_SalesRevenueGoodsNet	$ 2,952,896,000us-gaap_SalesRevenueGoodsNet	$ 2,821,446,000us-gaap_SalesRevenueGoodsNet
Consolidated segment assets	3,494,621,000us-gaap_Assets	3,331,731,000us-gaap_Assets
Operating profit	592,321,000us-gaap_OperatingIncomeLoss	516,339,000us-gaap_OperatingIncomeLoss	486,618,000us-gaap_OperatingIncomeLoss
Interest expense	(46,067,000)us-gaap_InterestExpense	(46,767,000)us-gaap_InterestExpense	(41,753,000)us-gaap_InterestExpense
Other expense, net	2,807,000us-gaap_OtherNonoperatingIncomeExpense	15,638,000us-gaap_OtherNonoperatingIncomeExpense	(1,450,000)us-gaap_OtherNonoperatingIncomeExpense
Income before taxes	549,061,000	485,210,000	443,415,000
Operating Profit Margin	19.20%iff_OperatingProfitMargin	17.50%iff_OperatingProfitMargin	17.20%iff_OperatingProfitMargin
Gain on the sale of non-operating asset		14,200,000us-gaap_GainLossOnDispositionOfAssets1
Restructuring and Other Charges, Net [Member]
Segment Reporting Information [Line Items]
Operating profit	(1,298,000)	(2,151,000)	(1,668,000)
Spanish Capital Tax Charge [Member]
Segment Reporting Information [Line Items]
Operating profit	0	(13,011,000)	0
Operational Improvement Initiative Costs [Member]
Segment Reporting Information [Line Items]
Operating profit	(7,642,000)	(8,770,000)	0
Flavors [Member]
Segment Reporting Information [Line Items]
Net sales	1,457,055,000	1,422,739,000	1,378,377,000
Consolidated segment assets	1,539,254,000	1,573,737,000
Operating profit	331,257,000	323,562,000	298,326,000
Operating Profit Margin	22.70%	22.70%	21.60%
Fragrances [Member]
Segment Reporting Information [Line Items]
Net sales	1,631,478,000	1,530,157,000	1,443,069,000
Consolidated segment assets	1,753,477,000	1,623,033,000
Operating profit	335,447,000	283,651,000	238,379,000
Operating Profit Margin	20.60%	18.50%	16.50%
Global assets [Member]
Segment Reporting Information [Line Items]
Consolidated segment assets	201,890,000	134,961,000
Global expenses [Member]
Segment Reporting Information [Line Items]
Operating profit	$ (65,443,000)	$ (66,942,000)	$ (48,419,000)

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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