Net Sales and Revenue (Details) - Schedule of Net Sales and Revenue for Each Product and Service Group - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015
Revenue from External Customer [Line Items]
Product or Service	$ 115,707	$ 113,480	$ 215,929	$ 218,677
Ethanol [Member]
Revenue from External Customer [Line Items]
Product or Service	90,933	86,990	168,564	165,562
Dried distillers grains [Member]
Revenue from External Customer [Line Items]
Product or Service	18,946	21,585	36,000	41,836
Non-food grade corn oil [Member]
Revenue from External Customer [Line Items]
Product or Service	4,738	4,049	8,584	8,008
Modified distillers grains [Member]
Revenue from External Customer [Line Items]
Product or Service	983	696	2,547	3,001
Other [Member]
Revenue from External Customer [Line Items]
Product or Service	$ 107	$ 160	$ 234	$ 270