COMMITMENTS (Detail) (USD $)	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Operating Leases, Future Minimum Payments Due	$ 4,921,000
Natural Gas Pipeline [Member] | One Earth Energy [Member]
Lease Expiration Period	10 years
Operating Leases, Future Minimum Payments Due	4,380,000
Number of installments payable	120
Installment amount	36,500
Operating Leases, Rent Expense, Net	438,000	438,000	438,000
Railcars One [Member] | One Earth Energy [Member]
Operating Leases, Rent Expense, Net	1,723,000	1,193,000	1,322,000
Lease Expiration Date	May 31, 2022
RailCars [Member] | Nu Gen Energy [Member]
Operating Leases, Rent Expense, Net	2,714,000	482,000
One Earth Energy And Nu Gen Energy [Member]
Quantity of Bushels under Forward Purchase Contract (in US Bushels)	16,900,000
Quantity of Ethanol under Sales Commitment (in US Gallons)	29,800,000
Quantity of Distillers Grains Under Sales Commitment (in US Ton)	60,000
Quantity of Non-food Grade Corn Oil Under Sales Commitments (in Pounds)	4,700,000
One Earth Energy [Member]
Marketing Expense	$ 627,000	$ 627,000
Percentage of Grain Purchase Under Agreement	100.00%	100.00%	100.00%
Expiration Date of Grain Agreement	Oct. 31, 2014
Maximum Period to Notify Other Party for Grain Agreement Period Extension	180 months