Segment Information, Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenue [Abstract]
Revenue	$ 347,513	$ 356,477
Operating income (loss)	49,420	55,681
Interest expense	5,402	5,555
Earnings before income taxes	44,018	50,126
Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	178,744	182,482
Operating income (loss)	23,125	25,327
Interest expense	0	0
Earnings before income taxes	23,125	25,327
Color [Member]
Revenue [Abstract]
Revenue	140,250	143,728
Operating income (loss)	30,199	33,672
Interest expense	0	0
Earnings before income taxes	30,199	33,672
Asia Pacific [Member]
Revenue [Abstract]
Revenue	28,519	30,267
Operating income (loss)	4,218	4,872
Interest expense	0	0
Earnings before income taxes	4,218	4,872
Reportable Segments [Member]
Revenue [Abstract]
Revenue	355,951	365,773
Reportable Segments [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	183,553	188,346
Reportable Segments [Member] \| Color [Member]
Revenue [Abstract]
Revenue	143,879	147,160
Reportable Segments [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	28,519	30,267
Intersegment Revenue [Member]
Revenue [Abstract]
Revenue	(8,438)	(9,296)
Intersegment Revenue [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	(4,809)	(5,864)
Intersegment Revenue [Member] \| Color [Member]
Revenue [Abstract]
Revenue	(3,629)	(3,432)
Intersegment Revenue [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	0	0
Corporate & Other [Member]
Revenue [Abstract]
Revenue	0	0
Operating income (loss)	(8,122)	(8,190)
Interest expense	5,402	5,555
Earnings before income taxes	$ (13,524)	$ (13,745)

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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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