Class of Warrant or Right, Disallowed Acquisition Of Additional Shares Outstanding Above Triggering Percentage

No definition available.

Name:	brn_ClassOfWarrantOrRightDisallowedAcquisitionOfAdditionalSharesOutstandingAboveTriggeringPercentage
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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

Class of Warrant or Right, Triggering Percentage

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Dividends Declared, Number Of Rights For Each Outstanding Share

+ References

No definition available.

+ Details

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Namespace Prefix:	brn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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Data Type:	dtr-types:perShareItemType
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Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=brn_LimitedDurationShareholderRightsPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

STOCKHOLDERS' EQUITY NARRATIVE (Details)	Jun. 30, 2025 $ / shares	Jan. 26, 2025 shares $ / shares	Sep. 30, 2024 $ / shares
Class of Warrant or Right [Line Items]
Common stock, par value (in dollars per share)	$ 0.50		$ 0.50
Limited-Duration Shareholder Rights Plan
Class of Warrant or Right [Line Items]
Number of rights for each outstanding share (in shares) \| shares		1
Common stock, par value (in dollars per share)		$ 0.50
Number of common stock purchased (in shares) \| shares		1
Exercise price of warrants or rights (in dollars per share)		$ 9.00
Triggering percentage		20.00%
Disallowed acquisition of additional shares outstanding above triggering percentage		0.25%