Debt Facilities Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jan. 31, 2016	Oct. 31, 2015	Mar. 31, 2016
Line of Credit Facility [Line Items]
Long-term Debt, Current Maturities	$ 584,674	$ 517,957
Long-term Debt, less current portion	7,536,806	6,711,975
Heron Lake Bioenergy [Member]
Line of Credit Facility [Line Items]
Long-term Debt	8,121,480	7,229,932
Long-term Debt, Current Maturities	584,674	517,957
Long-term Debt, less current portion	$ 7,536,806	6,711,975
Heron Lake Bioenergy [Member] | Revolving Term Loan [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	LIBOR
Agrinatural, LLC [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	$ 266,000	300,000
CoBank [Member] | Heron Lake Bioenergy [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	5,776,421	4,822,777
CoBank [Member] | Heron Lake Bioenergy [Member] | Revolving Operating Loan [Member] | Subsequent Event [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum borrowing capacity, superseded			$ 21,000,000
CoBank [Member] | Heron Lake Bioenergy [Member] | Revolving Term Loan [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	5,776,000	$ 4,823,000
Long-term Debt	28,000,000
Line of Credit Future Reduction, Amount	$ 3,500,000
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	3.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.50%
Line of Credit Facility, Maximum borrowing capacity, superseded	$ 24,500,000
Debt Instrument, Interest Rate During Period	3.69%	3.45%
City/County Juristiction [Member] | Heron Lake Bioenergy [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	$ 1,954,059	$ 1,963,405
City/County Juristiction [Member] | Heron Lake Bioenergy [Member] | Water Revenue Bonds [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 735,000
City/County Juristiction [Member] | Heron Lake Bioenergy [Member] | Water Treatment Plant [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum	0.50%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum	8.73%
Line of Credit Facility, Maximum Borrowing Capacity	$ 3,600,000
Federated Electric [Member] | Heron Lake Bioenergy [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amount Outstanding	125,000	143,750
Granite Falls Energy, LLC [Member]
Line of Credit Facility [Line Items]
Line of Credit Future Reduction, Amount	$ 2,000,000
Line of Credit Facility, Interest Rate Description	"One Month LIBOR Index Rate," plus 3.05%.
Granite Falls Energy, LLC [Member] | Savings Account Balance Requirement [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Covenant Description	0
Granite Falls Energy, LLC [Member] | Revolving Term Loan [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ 18,000,000
Line of Credit Facility, Maximum borrowing capacity, superseded	12,000,000	$ 12,000,000	$ 10,000,000
Heron Lake Bio-energy LLC [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ 8,121,480