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Derivative Instruments Narrative (Details) (USD $)
Oct. 31, 2014
Oct. 31, 2013
Margin requirements [Member]    
Derivative [Line Items]    
Restricted Cash and Cash Equivalents, Current $ 492,000us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
/ gfe_RestrictedcashtypeAxis
= gfe_MarginrequirementsMember
$ 394,000us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
/ gfe_RestrictedcashtypeAxis
= gfe_MarginrequirementsMember
Corn Contracts [Member]    
Derivative [Line Items]    
Outstanding corn derivative instrument 7,135,000gfe_OutstandingCornDerivativeInstrument
/ us-gaap_ProductOrServiceAxis
= gfe_CornContractsMember
1,125,000gfe_OutstandingCornDerivativeInstrument
/ us-gaap_ProductOrServiceAxis
= gfe_CornContractsMember
Granite Falls Energy [Member] | Margin requirements [Member]    
Derivative [Line Items]    
Restricted Cash and Cash Equivalents, Current 228,000us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= gfe_GraniteFallsEnergyMember
/ gfe_RestrictedcashtypeAxis
= gfe_MarginrequirementsMember
 
Granite Falls Energy [Member] | Corn Contracts [Member]    
Derivative [Line Items]    
Outstanding corn derivative instrument 4,345,000gfe_OutstandingCornDerivativeInstrument
/ dei_LegalEntityAxis
= gfe_GraniteFallsEnergyMember
/ us-gaap_ProductOrServiceAxis
= gfe_CornContractsMember
 
Heron Lake Bio-energy LLC [Member] | Margin requirements [Member]    
Derivative [Line Items]    
Restricted Cash and Cash Equivalents, Current $ 264,000us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= gfe_HeronLakeBioenergyLLCMember
/ gfe_RestrictedcashtypeAxis
= gfe_MarginrequirementsMember
 
Heron Lake Bio-energy LLC [Member] | Corn Contracts [Member]    
Derivative [Line Items]    
Outstanding corn derivative instrument 2,790,000gfe_OutstandingCornDerivativeInstrument
/ dei_LegalEntityAxis
= gfe_HeronLakeBioenergyLLCMember
/ us-gaap_ProductOrServiceAxis
= gfe_CornContractsMember