XML 128 R113.htm IDEA: XBRL DOCUMENT v3.25.3

Transactions With Related Parties - Incurred Amounts by Related Parties (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) asset	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) asset	Sep. 30, 2024 USD ($)
Convertible Notes
Related Party Transaction [Line Items]
Repurchase of aggregate principal amount		$ 33,800		$ 33,800
Revantage Corporate Services, LLC and Revantage Global Services Europe S.à r.l, EQ Management, LLC, BRE Hotels & Resorts, LLC LivCor, LLC, NNN PortCo - Reliant | Related Party
Related Party Transaction [Line Items]
Related party transaction	$ 3,830	422	$ 7,471	1,027
Brio Real Estate Services, LLC, Brio Real Estate (UK) Ltd And Brio Real Estate (AUS) Pty Ltd | Related Party
Related Party Transaction [Line Items]
Related party transaction	1,244	0	2,345	0
Revantage Corporate Services, LLC And Revantage Global Services Europe S.à r.l. | Related Party
Related Party Transaction [Line Items]
Related party transaction	353	384	696	945
Perform Properties, LLC | Related Party
Related Party Transaction [Line Items]
Related party transaction	1,903	38	2,797	82
LivCor LLC | Related Party
Related Party Transaction [Line Items]
Related party transaction	46	0	322	0
BRE Hotels & Resorts, LLC | Related Party
Related Party Transaction [Line Items]
Related party transaction	284	0	1,153	0
LendingOne | Related Party
Related Party Transaction [Line Items]
Related party transaction	0	0	158	0
Total | Related Party
Related Party Transaction [Line Items]
Related party transaction	897	165	2,170	337
BTIG, LLC | Related Party
Related Party Transaction [Line Items]
Related party transaction	0	84	0	124
Repurchase of aggregate principal amount			0
BTIG, LLC | Related Party | Senior secured notes, net
Related Party Transaction [Line Items]
Repurchase of aggregate principal amount				30,800
BTIG, LLC | Related Party | Convertible Notes
Related Party Transaction [Line Items]
Repurchase of aggregate principal amount				33,800
Gryphon Mutual Property Americas IC | Related Party
Related Party Transaction [Line Items]
Related party transaction	697	57	1,845	142
Insurance costs inclusive of premiums, capital surplus contributions, taxes and pro rata share of expenses			1,400	400
Gryphon Mutual Property Americas IC | Affiliates of Manager
Related Party Transaction [Line Items]
Management fees paid to manager			86	30
Blackstone internal audit services | Related Party
Related Party Transaction [Line Items]
Related party transaction	0	24	0	71
Lexington National Land Services | Related Party
Related Party Transaction [Line Items]
Related party transaction	170	0	216	0
Blackstone Securities Partners L.P | Related Party
Related Party Transaction [Line Items]
Related party transaction	$ 30	$ 0	$ 109	$ 0
CT Investment Management Co., LLC | Related Party
Related Party Transaction [Line Items]
Number of assets in special servicing under CLOs | asset	2		2

X

- Definition

Amount Contributed To Captive Towards Insurance Premium

+ References

No definition available.

+ Details

Name:	bxmt_AmountContributedToCaptiveTowardsInsurancePremium
Namespace Prefix:	bxmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Collateralized Loan Obligations, Number Of Assets

+ References

No definition available.

+ Details

Name:	bxmt_CollateralizedLoanObligationsNumberOfAssets
Namespace Prefix:	bxmt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

Name:	us-gaap_ExtinguishmentOfDebtAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount paid to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 230
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477867/946-230-45-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

+ Details

Name:	us-gaap_PaymentForManagementFee
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

Name:	us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

+ Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BrioRealEstateServicesLLCUKAUSPtyLtdRevantageCorporateAndGlobalServicesEuropeS.aR.l.PerformPropertiesLLCLivCorLLCBREHotelsResortsLLCLendingOneLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_RelatedPartyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BrioRealEstateServicesLLCBrioRealEstateUKLtdAndBrioRealEstateAUSPtyLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_RevantageCorporateServicesLLCAndRevantageGlobalServicesEuropeS.aR.l.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_PerformPropertiesLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_LivCorLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BREHotelsResortsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_LendingOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BTIGLLCGryphonMutualPropertyAmericasICInternalAuditServicesLexingtonNationalLandServicesBlackstoneSecuritiesPartnersL.PMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BTIGLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=bxmt_SeniorSecuredNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_GryphonMutualPropertyAmericaICGryphonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BlackstoneInternalAuditServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_LexingtonNationalLandServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_BlackstoneSecuritiesPartnersL.PMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=bxmt_CTInvestmentManagementCo.LLCCTIMCOMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: