No definition available.

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Number Of Directors

No definition available.

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Number Of Directors Eligible For Annual Compensation

No definition available.

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Number Of Loans Receivable Outstanding

No definition available.

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The percentage of Directors' compensation paid in the form of deferred stock units.

No definition available.

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The percentage of Directors' compensation paid in cash.

No definition available.

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Unfunded Commitments Related To Loans Receivable

No definition available.

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

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Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.14)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Balance Type:	debit
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Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
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Name:	us-gaap_TitleOfIndividualAxis=bxmt_AuditDirectorMember
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