Revenues - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Percentage of sales	100.00%	100.00%	100.00%	100.00%
Sales	$ 233,022	$ 345,215	$ 535,735	$ 660,110
United States
Disaggregation of Revenue [Line Items]
Sales	176,313	289,551	406,756	547,193
International
Disaggregation of Revenue [Line Items]
Sales	$ 56,709	$ 55,664	$ 128,979	$ 112,917
Nylon
Disaggregation of Revenue [Line Items]
Percentage of sales	22.00%	27.00%	24.00%	29.00%
Caprolactam
Disaggregation of Revenue [Line Items]
Percentage of sales	15.00%	20.00%	19.00%	20.00%
Ammonium Sulfate Fertilizers
Disaggregation of Revenue [Line Items]
Percentage of sales	34.00%	27.00%	28.00%	25.00%
Chemical Intermediates
Disaggregation of Revenue [Line Items]
Percentage of sales	29.00%	26.00%	29.00%	26.00%