Name:	hlb_ManagementServicesAgreementPercentageOfApplicableCompensation
Namespace Prefix:	hlb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Renewal period for management services agreement, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	hlb_ManagementServicesAgreementRenewalTerm
Namespace Prefix:	hlb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of management positions of related party partially paid for by entity based on management services agreement.

No definition available.

Name:	hlb_NumberOfManagementPositionsOfRelatedPartyPartiallyPaidForByEntity
Namespace Prefix:	hlb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The period for a written notice prior to the renewal of the Management Services Agreement required for termination of the Agreement with Granite Falls Energy, LLC.

No definition available.

Name:	hlb_RelatedPartyTransactionsManagementServicesAgreementPeriodOfWrittenNoticeForTerminationPriorToRenewalOfAgreement
Namespace Prefix:	hlb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of transactions with related party during the financial reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Name:	us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

No definition available.

Name:	us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=hlb_BoardMembersMember
Namespace Prefix:
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Balance Type:
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Name:	srt_ProductOrServiceAxis=hlb_CornMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RelatedPartyTransactionAxis=hlb_GraniteFallsEnergyLlcExcludingHeronLakeBioenergyLlcMember
Namespace Prefix:
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