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- References

No definition available.

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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.

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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.

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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.

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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.

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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
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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.

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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.

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Represents the amount of required debt repayments on renewal of credit facility for specified period.

No definition available.

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Number of Real Estate Properties Sold

No definition available.

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Real estate loan, additional dislosures [Abstract]

No definition available.

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The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

No definition available.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
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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.

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- References

No definition available.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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

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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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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

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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
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Amount of long-term debt, after 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.

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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.

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Cash received for the sale of real estate that is not part of an investing activity during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

No definition available.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

No definition available.

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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_RevolvingCreditFacilityMember
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