Derivative Instruments Narrative (Details)	Oct. 31, 2015 bu	Oct. 31, 2014 USD ($) bu
Margin requirements [Member]
Derivative [Line Items]
Restricted Cash and Cash Equivalents, Current \| $		$ 492,000
Corn Contracts [Member]
Derivative [Line Items]
Outstanding corn derivative instrument \| bu	2,615,000	7,135,000
Granite Falls Energy [Member] \| Margin requirements [Member]
Derivative [Line Items]
Restricted Cash and Cash Equivalents, Current \| $		$ 228,000
Granite Falls Energy [Member] \| Corn Contracts [Member]
Derivative [Line Items]
Outstanding corn derivative instrument \| bu	740,000	4,345,000
Heron Lake Bio-energy LLC [Member] \| Margin requirements [Member]
Derivative [Line Items]
Restricted Cash and Cash Equivalents, Current \| $		$ 264,000
Heron Lake Bio-energy LLC [Member] \| Corn Contracts [Member]
Derivative [Line Items]
Outstanding corn derivative instrument \| bu	1,875,000	2,790,000

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5

Name:	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant