Segment Information, Revenue from External Customers by Geographic Markets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue [Abstract]
Revenue	$ 356,477	$ 341,397
North America [Member]
Revenue [Abstract]
Revenue	182,637	183,856
Europe [Member]
Revenue [Abstract]
Revenue	89,064	78,891
Asia Pacific [Member]
Revenue [Abstract]
Revenue	53,943	50,418
Other [Member]
Revenue [Abstract]
Revenue	30,833	28,232
Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	182,482	181,075
Color [Member]
Revenue [Abstract]
Revenue	143,728	130,840
Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,267	29,482
Asia Pacific [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,267	29,482
Reportable Geographical Components [Member] | Flavors & Fragrances [Member] | North America [Member]
Revenue [Abstract]
Revenue	119,055	122,122
Reportable Geographical Components [Member] | Flavors & Fragrances [Member] | Europe [Member]
Revenue [Abstract]
Revenue	45,427	42,507
Reportable Geographical Components [Member] | Flavors & Fragrances [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	7,022	6,324
Reportable Geographical Components [Member] | Flavors & Fragrances [Member] | Other [Member]
Revenue [Abstract]
Revenue	10,978	10,122
Reportable Geographical Components [Member] | Color [Member] | North America [Member]
Revenue [Abstract]
Revenue	63,582	61,734
Reportable Geographical Components [Member] | Color [Member] | Europe [Member]
Revenue [Abstract]
Revenue	43,631	36,323
Reportable Geographical Components [Member] | Color [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	16,910	14,778
Reportable Geographical Components [Member] | Color [Member] | Other [Member]
Revenue [Abstract]
Revenue	19,605	18,005
Reportable Geographical Components [Member] | Asia Pacific [Member] | North America [Member]
Revenue [Abstract]
Revenue	0	0
Reportable Geographical Components [Member] | Asia Pacific [Member] | Europe [Member]
Revenue [Abstract]
Revenue	6	61
Reportable Geographical Components [Member] | Asia Pacific [Member] | Asia Pacific [Member]
Revenue [Abstract]
Revenue	30,011	29,316
Reportable Geographical Components [Member] | Asia Pacific [Member] | Other [Member]
Revenue [Abstract]
Revenue	$ 250	$ 105