CONSOLIDATED STATEMENT OF INCOME AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net sales	$ 1,198,773	$ 1,291,568	$ 2,546,090	$ 2,588,970
Cost of goods sold	716,931	745,329	1,498,381	1,511,472
Gross profit	481,842	546,239	1,047,709	1,077,498
Research and development expenses	80,948	84,816	166,857	175,412
Selling and administrative expenses	230,407	210,100	460,121	423,282
Amortization of acquisition-related intangibles	48,834	47,909	97,184	95,534
Restructuring and other charges, net	1,884	2,525	6,802	18,699
Losses on sales of fixed assets	399	952	1,153	764
Operating profit	119,370	199,937	315,592	363,807
Interest expense	32,062	32,593	64,202	69,165
Other income, net	(15,757)	(2,137)	(5,183)	(9,415)
Income before taxes	103,065	169,481	256,573	304,057
Taxes on income	15,699	30,612	41,996	53,974
Net income	87,366	138,869	214,577	250,083
Net income attributable to noncontrolling interests	1,162	2,492	3,766	4,877
Net income attributable to IFF stockholders	86,204	136,377	210,811	245,206
Other comprehensive income (loss), net, after tax:
Foreign currency translation adjustments	146,468	(14,014)	(305,810)	28,363
(Losses) gains on derivatives qualifying as hedges	(3,101)	415	(1,654)	318
Pension and postretirement net liability	3,375	2,594	6,892	5,187
Net current period other comprehensive income (loss)	146,742	(11,005)	(300,572)	33,868
Comprehensive income (loss) attributable to IFF stockholders	$ 232,946	$ 125,372	$ (89,761)	$ 279,074
Net income per share - basic (in dollars per share)	$ 0.75	$ 1.21	$ 1.91	$ 2.19
Net income per share - diluted (in dollars per share)	$ 0.74	$ 1.20	$ 1.89	$ 2.16
Average number of shares outstanding - basic (in shares)	112,177	111,996	112,130	111,930
Average number of shares outstanding - diluted (in shares)	113,675	112,872	113,635	113,131