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Nature of Operations and Summary of Significant Accounting Policies - Contract Assets, Receivables, and Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Receivables (included in Trade receivables)	$ 951,194		$ 951,194		$ 946,938
Contract asset - Short term	3,342		3,342		$ 487
Revenues	1,267,345	$ 907,548	3,856,315	$ 2,758,492
Flavor Compounds
Disaggregation of Revenue [Line Items]
Revenues	716,169	436,214	2,165,650	1,335,773
Fragrance Compounds
Disaggregation of Revenue [Line Items]
Revenues	389,757	379,359	1,154,564	1,130,028
Ingredients
Disaggregation of Revenue [Line Items]
Revenues	$ 161,419	$ 91,975	$ 536,101	$ 292,691