CONSOLIDATED STATEMENT OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Net sales	$ 3,088,533us-gaap_SalesRevenueGoodsNet	$ 2,952,896us-gaap_SalesRevenueGoodsNet	$ 2,821,446us-gaap_SalesRevenueGoodsNet
Cost of goods sold	1,726,383us-gaap_CostOfGoodsSold	1,668,691us-gaap_CostOfGoodsSold	1,645,912us-gaap_CostOfGoodsSold
Gross profit	1,362,150us-gaap_GrossProfit	1,284,205us-gaap_GrossProfit	1,175,534us-gaap_GrossProfit
Research and development expenses	253,640us-gaap_ResearchAndDevelopmentExpense	259,838us-gaap_ResearchAndDevelopmentExpense	233,713us-gaap_ResearchAndDevelopmentExpense
Selling and administrative expenses	514,891	505,877	453,535
Restructuring and other charges, net	1,298iff_RestructuringandOtherCharges	2,151iff_RestructuringandOtherCharges	1,668iff_RestructuringandOtherCharges
Operating profit	592,321us-gaap_OperatingIncomeLoss	516,339us-gaap_OperatingIncomeLoss	486,618us-gaap_OperatingIncomeLoss
Interest expense	46,067us-gaap_InterestExpense	46,767us-gaap_InterestExpense	41,753us-gaap_InterestExpense
Other (income) expense, net	(2,807)us-gaap_OtherNonoperatingIncomeExpense	(15,638)us-gaap_OtherNonoperatingIncomeExpense	1,450us-gaap_OtherNonoperatingIncomeExpense
Income before taxes	549,061	485,210	443,415
Taxes on income	134,518us-gaap_IncomeTaxExpenseBenefit	131,666us-gaap_IncomeTaxExpenseBenefit	189,281us-gaap_IncomeTaxExpenseBenefit
Net income	414,543us-gaap_NetIncomeLoss	353,544us-gaap_NetIncomeLoss	254,134us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Foreign currency translation adjustments	(69,064)	(10,556)	17,687
Gains (losses) on derivatives qualifying as hedges	16,383	(3,794)	(4,455)
Pension and postretirement liability adjustment	(95,038)	25,264	(41,548)
Comprehensive income	$ 266,824us-gaap_ComprehensiveIncomeNetOfTax	$ 364,458us-gaap_ComprehensiveIncomeNetOfTax	$ 225,818us-gaap_ComprehensiveIncomeNetOfTax
Net income per share - basic (in dollars per share)	$ 5.09us-gaap_EarningsPerShareBasic	$ 4.32us-gaap_EarningsPerShareBasic	$ 3.11us-gaap_EarningsPerShareBasic
Net income per share - diluted (in dollars per share)	$ 5.06us-gaap_EarningsPerShareDiluted	$ 4.29us-gaap_EarningsPerShareDiluted	$ 3.09us-gaap_EarningsPerShareDiluted

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Total costs related to goods produced and sold during the reporting period.

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