Commitments and Contingencies (Details)	1 Months Ended			12 Months Ended
	Nov. 30, 2016 USD ($)	Oct. 31, 2013 USD ($) gal	Oct. 31, 2005	Oct. 31, 2016 USD ($) MMBTU bu	Oct. 31, 2015 USD ($) mi	Oct. 31, 2014 USD ($)	Oct. 31, 2013 USD ($) gal	Oct. 31, 2007 USD ($)	Oct. 31, 2006 USD ($)
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Selling and Marketing Expense				$ 1,256,000	$ 1,234,000	$ 1,318,000
Percentage of revenues attributable to major customer				1.00%
Construction in Progress, Gross				$ 315,631	$ 2,013,765
Administrative fee to be paid as water usage fees (as a percent)		594000.00%
Natural Gas [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Pipeline | mi					9.5
Future Commitment, DT | MMBTU				1,400,000
Corn Oil [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Fees and Commissions				$ 166,000	$ 125,000	112,000
Distillers' Grains [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				P90D
Contract, Initial Length				P1Y
Fees and Commissions				$ 335,000	421,000	518,000
Heron Lake BioEnergy, LLC [Member] | Distillers' Grains [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Initial term of ethanol marketing agreement				6 months
Maximum period of written cancellation notice by either party				60 days
Distillers' grains commissions				$ 283,000	308,000	293,000
Granite Falls Energy, LLC [Member] | Corn Oil [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Dollar				$ 490,000
Future commitment, percent of anticipated usage				57.00%
Granite Falls Energy, LLC [Member] | Ethanol Contracts [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Dollar				$ 18,801,000
Revenue Concentration, Future Commitment				51.00%
Granite Falls Energy, LLC [Member] | Initial Length [Member] | Ethanol Contracts [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				December 31, 2019
Granite Falls Energy, LLC [Member] | Renewal Notice [Member] | Ethanol Contracts [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				P90M
Granite Falls Energy, LLC [Member] | Corn Oil [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				P90D
Contract, Initial Length				P1Y
Granite Falls Energy, LLC [Member] | Distillers' Grains [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Dollar				$ 1,595,000
Revenue Concentration, Future Commitment				40.00%
Heron Lake BioEnergy, LLC [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
City's water well bond payments		$ 735,000					$ 735,000
Operating and administrative/maintenance expenses paid		$ 12,000
Distance of the natural gas pipeline from the ethanol plant				$ 16
Heron Lake BioEnergy, LLC [Member] | Water supply development and distribution agreement
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Term of agreement		15 years
Initial volume per minute of capacity that is available from the well for which the entity has exclusive rights (in gallons) | gal		6,000					6,000
Administrative fee to be paid as water usage fees (as a percent)		5.00%
Percentage of profit to be paid as water usage fees		10.00%
Heron Lake BioEnergy, LLC [Member] | Water treatment agreement
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Term of agreement			30 years
Long-term debt		$ 367,000						$ 500,000	$ 3,550,000
Operating and administrative/maintenance expenses paid					$ 24,000	$ 57,000	$ 114,000
Heron Lake BioEnergy, LLC [Member] | Marketing, corn supply and corn storage agreements
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Percentage of ethanol and distillers grains products produced by the entity to be purchased, marketed and resold by Gavilon				100.00%
Heron Lake BioEnergy, LLC [Member] | Corn Oil [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				P90D
Future Commitment, Dollar				$ 630,000
Future commitment, percent of anticipated usage				76.00%
Heron Lake BioEnergy, LLC [Member] | Ethanol Contracts [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Dollar				$ 18,621,000
Revenue Concentration, Future Commitment				51.00%
Heron Lake BioEnergy, LLC [Member] | Corn Oil [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Written Notice				P90D
Contract, Initial Length				P1Y
Heron Lake BioEnergy, LLC [Member] | Distillers' Grains [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Future Commitment, Dollar				$ 2,863,000
Corn Contracts [Member] | Granite Falls Energy, LLC [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Inventory Dollars, Outside Storage				6,194,000
forward contracts	$ 900,000
Purchases For Inventory				$ 2,898,000
Inventory, Outside storage | bu				1,920,000
Corn Contracts [Member] | Heron Lake BioEnergy, LLC [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Inventory, Outside storage | bu				3,183,000