Deferred financing costs

No definition available.

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Namespace Prefix:	brmk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of the total principal payments made during the annual reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ Details

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- Definition

Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
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-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031898-161870

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Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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- Details

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Debt (Additional Information) (Details) - USD ($) $ in Thousands	Nov. 12, 2021	Feb. 19, 2021	Jun. 30, 2022	Dec. 31, 2021
Line of Credit Facility [Line Items]
Aggregate principal amount			$ 100,000	$ 100,000
Debt issuance cost			97,503	97,223
5.0% senior unsecured notes due 2026 \| Private offering [Member]
Line of Credit Facility [Line Items]
Aggregate principal amount	$ 100,000
Fixed interest rate	5.00%
Debt issuance cost	$ 2,900
5.0% senior unsecured notes due 2026 \| Private offering [Member] \| Future [Member]
Line of Credit Facility [Line Items]
Maturity Date	Nov. 15, 2026
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Amount of revolving credit facility		$ 135,000
Maturity Date		Feb. 19, 2024
Amortization period		3 years
Revolving credit facility outstanding, amount			$ 0	$ 0
Deferred financing costs		$ 4,500