Document and Entity Information - shares	6 Months Ended
	Apr. 30, 2020	Jun. 15, 2020
Cover [Abstract]
Document Type	10-Q
Document Period End Date	Apr. 30, 2020
Entity Registrant Name	Granite Falls Energy, LLC
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Interactive Data Current	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		30,606
Current Fiscal Year End Date	--10-31
Entity Central Index Key	0001181749
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false