Segment Information, Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue [Abstract]
Revenue	$ 350,677	$ 347,513
Operating income (loss)	34,561	49,420
Interest expense	4,307	5,402
Earnings before income taxes	30,254	44,018
Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	181,187	178,744
Operating income (loss)	20,871	23,125
Interest expense	0	0
Earnings before income taxes	20,871	23,125
Color [Member]
Revenue [Abstract]
Revenue	139,193	140,250
Operating income (loss)	29,664	30,199
Interest expense	0	0
Earnings before income taxes	29,664	30,199
Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,297	28,519
Operating income (loss)	5,059	4,218
Interest expense	0	0
Earnings before income taxes	5,059	4,218
Reportable Segments [Member]
Revenue [Abstract]
Revenue	360,442	355,951
Reportable Segments [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	186,498	183,553
Reportable Segments [Member] \| Color [Member]
Revenue [Abstract]
Revenue	143,495	143,879
Reportable Segments [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,449	28,519
Intersegment Revenue [Member]
Revenue [Abstract]
Revenue	9,765	8,438
Intersegment Revenue [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	5,311	4,809
Intersegment Revenue [Member] \| Color [Member]
Revenue [Abstract]
Revenue	4,302	3,629
Intersegment Revenue [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	152	0
Corporate & Other [Member]
Revenue [Abstract]
Revenue	0	0
Operating income (loss)	(21,033)	(8,122)
Interest expense	4,307	5,402
Earnings before income taxes	$ (25,340)	$ (13,524)

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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

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