MEMBERS' EQUITY (Details)		1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 11, 2019 USD ($)	Dec. 31, 2018 USD ($) $ / shares	Jan. 31, 2020 USD ($)	Jan. 31, 2019 USD ($)	Jul. 31, 2020 item $ / shares shares	Jul. 31, 2019 $ / shares	Oct. 31, 2019 USD ($) shares
Common Units Authorized | shares					30,606		30,606
Common Units Issued | shares					30,606		30,606
Common Units Outstanding | shares					30,606		30,606
Distribution per unit declared (in dollars per unit) | $ / shares						$ 40.00
Amount of distribution declared | $				$ 1,224,226
Remaining non-controlling interest | $			$ 2,225,000
Non-controlling Interest
Remaining non-controlling interest | $			$ 2,146,183
Granite Falls Energy, LLC Excluding Heron Lake BioEnergy, LLC
Number of classes of membership units | item					1
Membership Units, Par value | $ / shares					$ 0
Common Units Authorized | shares					30,606		30,606
Common Units Issued | shares					30,606		30,606
Common Units Outstanding | shares					30,606		30,606
Distribution per unit declared (in dollars per unit) | $ / shares		$ 40
Amount of distribution declared | $		$ 1,224,000
Heron Lake BioEnergy, LLC
Remaining non-controlling interest | $	$ 2,225,000
Heron Lake BioEnergy, LLC | Other assets
Deposit Assets | $							$ 225,000