Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Jul. 31, 2013 bu
Corn Contracts [Member]
Future Commitment	1,455,000
Inventory, Outside storage	375,000
Inventory Dollars, Outside Storage	$ 2,775,000
Ethanol Contracts [Member]
Future Commitment, Dollar	15,980,000
Revenue Concentration, Future Commitment	29.00%
Distillers Grains [Member]
Future Commitment, Dollar	$ 1,580,000
Revenue Concentration, Future Commitment	17.00%
Heron Lake Bioenergy [Member]
Purchase Commitment, Remaining Minimum Amount Committed	1,600,000