Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Sales	$ 89,096	$ 87,956
Distillery products
Disaggregation of Revenue [Line Items]
Sales	74,577	74,377
Ingredient solutions
Disaggregation of Revenue [Line Items]
Sales	14,519	13,579
Premium beverage alcohol | Distillery products
Disaggregation of Revenue [Line Items]
Sales	42,009	44,071
Brown Goods | Distillery products
Disaggregation of Revenue [Line Items]
Sales	24,827	28,201
White Goods | Distillery products
Disaggregation of Revenue [Line Items]
Sales	17,182	15,870
Industrial alcohol | Distillery products
Disaggregation of Revenue [Line Items]
Sales	20,443	19,344
Food grade alcohol | Distillery products
Disaggregation of Revenue [Line Items]
Sales	62,452	63,415
Fuel grade alcohol | Distillery products
Disaggregation of Revenue [Line Items]
Sales	1,501	1,863
Distillers feed and related co-products | Distillery products
Disaggregation of Revenue [Line Items]
Sales	7,095	6,224
Warehouse services | Distillery products
Disaggregation of Revenue [Line Items]
Sales	3,529	2,875
Specialty wheat starches | Ingredient solutions
Disaggregation of Revenue [Line Items]
Sales	6,881	6,801
Specialty wheat proteins | Ingredient solutions
Disaggregation of Revenue [Line Items]
Sales	4,442	4,736
Commodity wheat starches | Ingredient solutions
Disaggregation of Revenue [Line Items]
Sales	2,262	2,042
Commodity wheat proteins | Ingredient solutions
Disaggregation of Revenue [Line Items]
Sales	$ 934	$ 0