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Risks and Uncertainties Narrative (Details)
 3 Months Ended 12 Months Ended
Jan. 31, 2014
Oct. 31, 2014
Concentration Risk [Line Items]    
Sales Revenue, Goods, Net, Percentage 100.00%us-gaap_ConcentrationRiskPercentage1  
Minimum [Member]    
Concentration Risk [Line Items]    
Sales Revenue, Goods, Net, Percentage   75.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Minimum [Member] | Corn Contracts [Member]    
Concentration Risk [Line Items]    
Percent of Cost of Goods Sold   65.00%gfe_PercentOfCostOfGoodsSold
/ us-gaap_ConcentrationRiskByTypeAxis
= gfe_CornContractsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Maximum [Member]    
Concentration Risk [Line Items]    
Sales Revenue, Goods, Net, Percentage   85.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Percent of Cost of Goods Sold   85.00%gfe_PercentOfCostOfGoodsSold
/ us-gaap_RangeAxis
= us-gaap_MaximumMember