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Represents the number of periodic repayments that would be due within the next twelve months.

No definition available.

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- Details

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Represents the percentage of outstanding loan balance to be repaid in final quarter of second year of the term period if the facility is converted to a two-year term loan subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityConversionRepaymentPercentageInFinalQuarterOfYearTwo
Namespace Prefix:	brn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of outstanding loan balance to be repaid per quarter for first three quarters in second year of the term period if the facility is converted to a two-year term loan subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityConversionRepaymentPercentagePerQuarterForFirstThreeQuartersOfYearTwo
Namespace Prefix:	brn_
Data Type:	num:percentItemType
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Represents the percentage of outstanding loan balance to be repaid per quarter in first year of the term period if the facility is converted to a two-year term loan subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityConversionRepaymentPercentagePerQuarterYearOne
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Represents the percentage of outstanding loan balance to be repaid in first year of the term period if the facility is converted to a two-year term loan subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityConversionRepaymentPercentageYearOne
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Balance Type:	na
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Represents the percentage of outstanding loan balance to be repaid in second year of the term period if the facility is converted to a two-year term loan subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityConversionRepaymentPercentageYearTwo
Namespace Prefix:	brn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the term loan period into which the line of credit facility will be converted if term date is not extended upon annual review.

No definition available.

Name:	brn_LineOfCreditFacilityConversionToTermLoanPeriod
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Data Type:	xbrli:durationItemType
Balance Type:	na
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Represents the percentage of the outstanding loan balance included in the current portion of long-term debt.

No definition available.

Name:	brn_LineOfCreditFacilityPercentageOfOutstandingLoanBalanceIncludedInLongTermDebtCurrent
Namespace Prefix:	brn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the period for which no debt repayments are required if the facility is renewed subject to annual review under the financing agreement.

No definition available.

Name:	brn_LineOfCreditFacilityRenewalPeriodWithNoRequiredDebtRepayments
Namespace Prefix:	brn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The effective interest rate at the end of the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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Data Type:	xbrli:stringItemType
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- Details

Name:	us-gaap_DebtInstrumentsAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The effective interest rate at the end of the reporting period.

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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Regulation S-X (SX)

-Number 210

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Number 210

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Topic 944

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Publisher SEC

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Name:	us-gaap_LongTermDebtCurrent
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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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