Nature of Operations and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenue	$ 3,977,539	$ 3,398,719	$ 3,116,350
Flavors [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,990,985	1,632,166	1,496,525
Fragrances [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,496,493	1,424,612	1,303,653
Fragrance Ingredients [Member]
Disaggregation of Revenue [Line Items]
Revenue	490,061	341,941	316,172
Europe, Africa and Middle East [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,396,315	1,065,596	964,931
Greater Asia [Member]
Disaggregation of Revenue [Line Items]
Revenue	991,015	903,546	880,040
North America [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,010,126	901,821	769,081
Latin America [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 580,083	$ 527,756	$ 502,298