MEMBERS' EQUITY (Details)		1 Months Ended		12 Months Ended
	Dec. 21, 2017 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) $ / shares	Oct. 31, 2019 USD ($) item $ / shares shares	Oct. 31, 2018 USD ($) $ / shares shares	Oct. 31, 2017 USD ($) $ / shares shares
Number of classes of membership units | item				1
Membership Units, Par value | $ / shares				$ 0
Common Units Authorized | shares				30,606	30,606	30,606
Common Units Issued | shares				30,606	30,606	30,606
Common Units Outstanding | shares				30,606	30,606	30,606
Distribution per unit declared (in dollars per unit) | $ / shares				$ 40.00	$ 385.00	$ 365.00
Amount of distribution declared | $				$ 1,224,226	$ 16,090,294	$ 11,171,190
Non-controlling Interest
Amount of distribution declared | $					$ 4,311,192
Granite Falls Energy, LLC Excluding Heron Lake BioEnergy, LLC
Distribution per unit declared (in dollars per unit) | $ / shares		$ 40	$ 385
Amount of distribution declared | $		$ 1,224,000	$ 11,783,000
Heron Lake BioEnergy, LLC
Distribution per unit declared (in dollars per unit) | $ / shares	$ 0.11
Amount of distribution declared | $	$ 8,573,000