Segment Information, Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue [Abstract]
Revenue	$ 323,566	$ 317,650	$ 997,333	$ 1,004,349
Operating income (loss)	41,155	38,788	117,841	135,576
Interest expense	3,497	4,936	11,412	15,538
Earnings before income taxes	37,658	33,852	106,429	120,038
Flavors & Extracts [Member]
Revenue [Abstract]
Revenue	179,687	163,870	539,304	517,148
Operating income (loss)	23,844	17,600	67,467	60,775
Interest expense	0	0	0	0
Earnings before income taxes	23,844	17,600	67,467	60,775
Color [Member]
Revenue [Abstract]
Revenue	113,139	123,710	369,211	399,610
Operating income (loss)	23,559	23,436	75,486	81,512
Interest expense	0	0	0	0
Earnings before income taxes	23,559	23,436	75,486	81,512
Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,740	30,070	88,818	87,591
Operating income (loss)	6,123	5,406	16,031	13,825
Interest expense	0	0	0	0
Earnings before income taxes	6,123	5,406	16,031	13,825
Reportable Segments [Member]
Revenue [Abstract]
Revenue	330,020	324,707	1,023,242	1,028,706
Reportable Segments [Member] | Flavors & Extracts [Member]
Revenue [Abstract]
Revenue	182,866	167,577	552,975	531,264
Reportable Segments [Member] | Color [Member]
Revenue [Abstract]
Revenue	116,414	127,005	381,205	409,796
Reportable Segments [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,740	30,125	89,062	87,646
Intersegment Revenue [Member]
Revenue [Abstract]
Revenue	6,454	7,057	25,909	24,357
Intersegment Revenue [Member] | Flavors & Extracts [Member]
Revenue [Abstract]
Revenue	3,179	3,707	13,671	14,116
Intersegment Revenue [Member] | Color [Member]
Revenue [Abstract]
Revenue	3,275	3,295	11,994	10,186
Intersegment Revenue [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	0	55	244	55
Corporate & Other [Member]
Revenue [Abstract]
Revenue	0	0	0	0
Operating income (loss)	(12,371)	(7,654)	(41,143)	(20,536)
Interest expense	3,497	4,936	11,412	15,538
Earnings before income taxes	$ (15,868)	$ (12,590)	$ (52,555)	$ (36,074)