Commitments, Contingencies and Guarantees - Additional Information (Details) $ in Millions			3 Months Ended		12 Months Ended
	Mar. 08, 2018 USD ($)	Jan. 17, 2017 USD ($)	Mar. 31, 2019 USD ($) T	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Annual purchase commitment, in tons | T			240,000
Commitments			$ 240.1
Outstanding guarantees and letters of credit			5.2
Estimated minimum compensatory punitive damages			$ 20.0
Agro Bio Sciences Inc
Commitments And Contingencies Disclosure [Line Items]
Payment year of achieving certain operating performance		2019
Payment to be made if certain operating performance is achieved		$ 17.8		$ 17.8
Passport Food Safety Solutions, Inc.
Commitments And Contingencies Disclosure [Line Items]
Payment year of achieving certain operating performance			2020
Payment to be made if certain operating performance is achieved	$ 7.3		$ 7.3
Maximum | Agro Bio Sciences Inc
Commitments And Contingencies Disclosure [Line Items]
Additional earn-out payment		$ 25.0
Maximum | Passport Food Safety Solutions, Inc.
Commitments And Contingencies Disclosure [Line Items]
Additional earn-out payment	$ 25.0		$ 25.0
Updated Sales Forecasts | Agro Bio Sciences Inc
Commitments And Contingencies Disclosure [Line Items]
Payment to be made if certain operating performance is achieved				23.2	$ 15.7
Updated Sales Forecasts | Selling, General and Administrative Expenses | Specialty Products | Agro Bio Sciences Inc
Commitments And Contingencies Disclosure [Line Items]
Increase (decrease) in estimate of contingent consideration liability				$ 5.4	$ (7.5)