RISKS AND UNCERTAINTIES Narrative (Details)	6 Months Ended
Apr. 30, 2020 USD ($)
Concentration Risk
Write down of inventory and impairment of purchase contract	$ 179,000

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels and impairment of corn forward purchase contracts.

No definition available.

Name:	gfe_InventoryWriteDownAndImpairmentOfPurchaseContract
Namespace Prefix:	gfe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration