$BXMT
BLACKSTONE MORTGAGE TRUST, INC. Stock $bxmt

$bxmt Overview Financials Valuation SEC Filings Company Website

2024 Q4 Form 10-Q Financial Statement

#000106163024000148 Filed on October 23, 2024

Income Statement

Concept	2024 Q4	2024 Q3	2023 Q3
Revenue		$430.1M	$519.3M
YoY Change		-17.19%	44.84%
Cost Of Revenue		$340.3M	$382.9M
YoY Change		-11.1%	67.71%
Gross Profit		$89.74M	$136.5M
YoY Change		-34.25%	4.77%
Gross Profit Margin		20.87%	26.28%
Selling, General & Admin		$14.42M	$10.64M
YoY Change		35.48%	-2.47%
% of Gross Profit		16.07%	7.8%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization		$1.029M
YoY Change
% of Gross Profit		1.15%
Operating Expenses		$148.6M	$12.00M
YoY Change		1138.04%	-7.2%
Operating Profit		-$58.83M	$124.5M
YoY Change		-147.26%	6.09%
Interest Expense			$354.0M
YoY Change			74.92%
% of Operating Profit			284.37%
Other Income/Expense, Net
YoY Change
Pretax Income		-$55.23M	$32.13M
YoY Change		-271.91%	-69.43%
Income Tax		$613.0K	$1.600M
% Of Pretax Income			4.98%
Net Earnings		-$56.38M	$29.52M
YoY Change		-290.98%	-71.4%
Net Earnings / Revenue		-13.11%	5.68%
Basic Earnings Per Share		-$0.32	$0.17
Diluted Earnings Per Share		-$0.32	$0.17
COMMON SHARES
Basic Shares Outstanding	173.0M shares	173.6M shares	172.3M shares
Diluted Shares Outstanding		173.6M shares	172.6M shares

Balance Sheet

Concept	2024 Q3	2023 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$322.1M	$421.5M
YoY Change	-23.58%	55.02%
Cash & Equivalents	$322.1M	$421.5M
Short-Term Investments
Other Short-Term Assets	$132.0M	$63.68M
YoY Change	107.26%	1393.18%
Inventory
Prepaid Expenses
Receivables	$176.0M	$189.6M
Other Receivables	$0.00	$0.00
Total Short-Term Assets	$630.1M	$674.8M
YoY Change	-6.62%	59.51%
LONG-TERM ASSETS
Property, Plant & Equipment	$138.7M
YoY Change
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets	$20.81B	$23.37B
YoY Change	-10.94%	-4.13%
TOTAL ASSETS
Total Short-Term Assets	$630.1M	$674.8M
Total Long-Term Assets	$20.81B	$23.37B
Total Assets	$21.44B	$24.04B
YoY Change	-10.81%	-3.05%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$8.662M	$7.742M
YoY Change	11.88%	6.46%
Accrued Expenses	$92.77M	$99.61M
YoY Change	-6.86%	19.16%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$13.62M
YoY Change	-100.0%	46.89%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$182.7M	$227.8M
YoY Change	-19.78%	10.53%
LONG-TERM LIABILITIES
Long-Term Debt	$17.24B	$19.27B
YoY Change	-10.56%	-3.18%
Other Long-Term Liabilities	$163.6M	$50.23M
YoY Change	225.78%	1430.97%
Total Long-Term Liabilities	$17.40B	$19.32B
YoY Change	-9.95%	-2.95%
TOTAL LIABILITIES
Total Short-Term Liabilities	$182.7M	$227.8M
Total Long-Term Liabilities	$17.40B	$19.32B
Total Liabilities	$17.58B	$19.55B
YoY Change	-10.06%	-2.81%
SHAREHOLDERS EQUITY
Retained Earnings	-$1.690B	-$1.041B
YoY Change	62.31%	27.8%
Common Stock	$5.523B	$5.501B
YoY Change	0.4%	0.59%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$3.845B	$4.471B
YoY Change
Total Liabilities & Shareholders Equity	$21.44B	$24.04B
YoY Change	-10.81%	-3.05%

Cashflow Statement

Concept	2024 Q3	2023 Q3
OPERATING ACTIVITIES
Net Income	-$56.38M	$29.52M
YoY Change	-290.98%	-71.4%
Depreciation, Depletion And Amortization	$1.029M
YoY Change
Cash From Operating Activities	$87.12M	$111.0M
YoY Change	-21.51%	33.7%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions
YoY Change
Other Investing Activities	$1.286B	$448.4M
YoY Change	186.81%	119.4%
Cash From Investing Activities	$1.286B	$448.4M
YoY Change	186.81%	119.4%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-1.426B	-619.0M
YoY Change	130.41%	111.54%
NET CHANGE
Cash From Operating Activities	87.12M	111.0M
Cash From Investing Activities	1.286B	448.4M
Cash From Financing Activities	-1.426B	-619.0M
Net Change In Cash	-52.92M	-59.55M
YoY Change	-11.13%	1044.95%
FREE CASH FLOW
Cash From Operating Activities	$87.12M	$111.0M
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Entity Central Index Key EntityCentralIndexKey	0001061630
	dei	Amendment Flag AmendmentFlag	false
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2024
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2024Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	172988799	shares
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	350014000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
	dei	Entity Address City Or Town EntityAddressCityOrTown	New York
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	9454000	usd
CY2024Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1689534000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	4367711000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1150934000	usd
CY2024Q3	us-gaap	Minority Interest MinorityInterest	15805000	usd
CY2024Q3	us-gaap	Stockholders Equity StockholdersEquity	3844592000	usd
CY2023Q4	us-gaap	Minority Interest MinorityInterest	19793000	usd
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3860397000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4387504000	usd
CY2024Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	21443194000	usd
CY2024Q3	us-gaap	Senior Notes SeniorNotes	333023000	usd
CY2024Q3	us-gaap	Other Liabilities OtherLiabilities	346382000	usd
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	173209933	shares
CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	173209933	shares
CY2024Q3	us-gaap	Common Stock Value CommonStockValue	1730000	usd
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	1732000	usd
CY2024Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	5521305000	usd
CY2023Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	5507459000	usd
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	11091000	usd
	dei	Entity Shell Company EntityShellCompany	false
CY2024Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	322104000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	476088000	usd
	dei	Entity Address Address Line1 EntityAddressAddressLine1	345 Park Avenue
CY2024Q3	us-gaap	Secured Debt SecuredDebt	2089715000	usd
	dei	Entity Address State Or Province EntityAddressStateOrProvince	NY
CY2023Q4	us-gaap	Assets Assets	24036178000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2023Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	0	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	390907000	usd
CY2024Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies	0	usd
CY2023Q4	bxmt	Loan Participations Sold Liability Amount LoanParticipationsSoldLiabilityAmount	337179000	usd
	dei	Entity Registrant Name EntityRegistrantName	Blackstone Mortgage Trust, Inc.
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	24036178000	usd
CY2024Q3	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	430092000	usd
CY2023Q3	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	519342000	usd
CY2023Q4	us-gaap	Secured Debt SecuredDebt	2101632000	usd
CY2024Q3	us-gaap	Convertible Notes Payable ConvertibleNotesPayable	263334000	usd
CY2023Q4	us-gaap	Convertible Notes Payable ConvertibleNotesPayable	295847000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	362531000	usd
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies	0	usd
	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	1382367000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	1004854000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	1015718000	usd
CY2024Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	321744000	usd
CY2023Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	353972000	usd
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	10154
	dei	Trading Symbol TradingSymbol	BXMT
	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2024Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	138725000	usd
CY2024Q3	us-gaap	Assets Assets	21443194000	usd
CY2024Q3	bxmt	Loan Participations Sold Liability Amount LoanParticipationsSoldLiabilityAmount	103489000	usd
CY2024Q3	us-gaap	Liabilities Liabilities	17582797000	usd
CY2023Q4	us-gaap	Liabilities Liabilities	19648674000	usd
	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	1532618000	usd
CY2024Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2024Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2024Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	172987597	shares
CY2024Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	172987597	shares
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3860397000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4544200000	usd
CY2023Q1	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7492000	usd
CY2023Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	287000	usd
CY2023Q1	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	163000	usd
CY2023Q1	us-gaap	Profit Loss ProfitLoss	118556000	usd
CY2023Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2194000	usd
CY2023Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q1	us-gaap	Dividends Dividends	107072000	usd
CY2023Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	733000	usd
CY2023Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4560699000	usd
CY2023Q2	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7492000	usd
CY2023Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	235000	usd
CY2023Q2	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	173000	usd
CY2023Q2	us-gaap	Profit Loss ProfitLoss	102497000	usd
CY2023Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	2912000	usd
CY2023Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q2	us-gaap	Dividends Dividends	107028000	usd
CY2023Q2	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	791000	usd
CY2023Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4566189000	usd
CY2023Q3	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7434000	usd
CY2023Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	245000	usd
CY2023Q3	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	172000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	30560000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-134000	usd
CY2023Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q3	us-gaap	Dividends Dividends	107033000	usd
CY2023Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	3912000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	24058000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	22926000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	50568000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	60333000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	security_loan
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	security_loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23923719000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024Q3	us-gaap	Loans Receivable Basis Spread On Variable Rate LoansReceivableBasisSpreadOnVariableRate	0.034
CY2023Q4	us-gaap	Loans Receivable Basis Spread On Variable Rate LoansReceivableBasisSpreadOnVariableRate	0.0337
	bxmt	Financing Receivable Basis Spread On Variable Rate Weighted Average All In Yield FinancingReceivableBasisSpreadOnVariableRateWeightedAverageAllInYield	0.0374
CY2023	bxmt	Financing Receivable Basis Spread On Variable Rate Weighted Average All In Yield FinancingReceivableBasisSpreadOnVariableRateWeightedAverageAllInYield	0.0371
	bxmt	Mortgage Loan On Real Estate Final Maturity Term MortgageLoanOnRealEstateFinalMaturityTerm	P2Y2M12D
CY2023	bxmt	Mortgage Loan On Real Estate Final Maturity Term MortgageLoanOnRealEstateFinalMaturityTerm	P2Y6M
CY2024Q3	bxmt	Financing Receivable Percent Of Loans Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansSubjectToPrepaymentRestrictions	0.14
CY2024Q3	bxmt	Financing Receivable Percent Of Loans Not Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansNotSubjectToPrepaymentRestrictions	0.86
CY2023Q4	bxmt	Financing Receivable Percent Of Loans Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansSubjectToPrepaymentRestrictions	0.14
CY2023Q4	bxmt	Financing Receivable Percent Of Loans Not Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansNotSubjectToPrepaymentRestrictions	0.86
CY2023Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-136707000	usd
	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
CY2023	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
CY2023	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
CY2023	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
CY2023	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
	us-gaap	Debt Instrument Variable Interest Rate Type Extensible Enumeration DebtInstrumentVariableInterestRateTypeExtensibleEnumeration	http://fasb.org/us-gaap/2024#SecuredOvernightFinancingRateSofrMember
	dei	Document Period End Date DocumentPeriodEndDate	2024-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-14788
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MD
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	94-6181186
	dei	Entity Address Address Line2 EntityAddressAddressLine2	24th Floor
	dei	City Area Code CityAreaCode	212
	dei	Local Phone Number LocalPhoneNumber	655-0220
	dei	Security12b Title Security12bTitle	Class A common stock, par value $0.01 per share
CY2023Q4	us-gaap	Senior Notes SeniorNotes	362763000	usd
CY2023Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2024Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	321744000	usd
CY2023Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	353972000	usd
CY2024Q3	bxmt	Interest And Fee Income Loans And Leases Net Of Interest Expense Operating InterestAndFeeIncomeLoansAndLeasesNetOfInterestExpenseOperating	108348000	usd
CY2023Q3	bxmt	Interest And Fee Income Loans And Leases Net Of Interest Expense Operating InterestAndFeeIncomeLoansAndLeasesNetOfInterestExpenseOperating	165370000	usd
	bxmt	Interest And Fee Income Loans And Leases Net Of Interest Expense Operating InterestAndFeeIncomeLoansAndLeasesNetOfInterestExpenseOperating	377513000	usd
	bxmt	Interest And Fee Income Loans And Leases Net Of Interest Expense Operating InterestAndFeeIncomeLoansAndLeasesNetOfInterestExpenseOperating	516900000	usd
CY2024Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1214000	usd
CY2023Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1214000	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
CY2024Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	2389000	usd
CY2023Q3	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4541000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	5352000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4541000	usd
CY2024Q3	us-gaap	Noninterest Income NoninterestIncome	111951000	usd
CY2023Q3	us-gaap	Noninterest Income NoninterestIncome	169911000	usd
	us-gaap	Noninterest Income NoninterestIncome	384079000	usd
	us-gaap	Noninterest Income NoninterestIncome	521441000	usd
CY2024Q3	us-gaap	Management Fee Expense ManagementFeeExpense	18605000	usd
CY2023Q3	us-gaap	Management Fee Expense ManagementFeeExpense	28882000	usd
	us-gaap	Management Fee Expense ManagementFeeExpense	56258000	usd
	us-gaap	Management Fee Expense ManagementFeeExpense	92747000	usd
CY2024Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	13423000	usd
CY2023Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	12001000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	40811000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	37888000	usd
CY2024Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	2684000	usd
CY2023Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	3647000	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
CY2024Q3	us-gaap	Noninterest Expense NoninterestExpense	34712000	usd
CY2023Q3	us-gaap	Noninterest Expense NoninterestExpense	40883000	usd
	us-gaap	Noninterest Expense NoninterestExpense	100716000	usd
	us-gaap	Noninterest Expense NoninterestExpense	130635000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	132470000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	96900000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	519747000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	134530000	usd
CY2024Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-55231000	usd
CY2023Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	32128000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-236384000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	256276000	usd
CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	613000	usd
CY2023Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1568000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2832000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4663000	usd
CY2024Q3	us-gaap	Profit Loss ProfitLoss	-55844000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	30560000	usd
	us-gaap	Profit Loss ProfitLoss	-239216000	usd
	us-gaap	Profit Loss ProfitLoss	251613000	usd
CY2024Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	540000	usd
CY2023Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	1036000	usd
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	2063000	usd
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	2681000	usd
CY2024Q3	us-gaap	Net Income Loss NetIncomeLoss	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss NetIncomeLoss	29524000	usd
	us-gaap	Net Income Loss NetIncomeLoss	-241279000	usd
	us-gaap	Net Income Loss NetIncomeLoss	248932000	usd
CY2024Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.32
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.17
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.39
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.44
CY2024Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.32
CY2023Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.17
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.39
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173637101	shares
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172648118	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173881116	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172620799	shares
CY2024Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	173637101	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172648118	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	173881116	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	180891859	shares
CY2024Q3	us-gaap	Profit Loss ProfitLoss	-55844000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	30560000	usd
	us-gaap	Profit Loss ProfitLoss	-239216000	usd
	us-gaap	Profit Loss ProfitLoss	251613000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	91072000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-71782000	usd
	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	49009000	usd
	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-21455000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-90309000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	71648000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-47372000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	22039000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	763000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-134000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	1637000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	584000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-55081000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	30426000	usd
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-237579000	usd
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	252197000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	540000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	1036000	usd
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	2063000	usd
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	2681000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-55621000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	29390000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-239642000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	249516000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4387504000	usd
CY2024Q1	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7911000	usd
CY2024Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	253000	usd
CY2024Q1	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	201000	usd
CY2024Q1	us-gaap	Profit Loss ProfitLoss	-123170000	usd
CY2024Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	416000	usd
CY2024Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2024Q1	us-gaap	Dividends Dividends	107901000	usd
CY2024Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	627000	usd
CY2024Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4164587000	usd
CY2024Q2	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7761000	usd
CY2024Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	261000	usd
CY2024Q2	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	201000	usd
CY2024Q2	us-gaap	Profit Loss ProfitLoss	-60202000	usd
CY2024Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	458000	usd
CY2024Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2024Q2	us-gaap	Dividends Dividends	107873000	usd
CY2024Q2	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	1245000	usd
CY2024Q2	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	1840000	usd
CY2024Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4004598000	usd
CY2024Q3	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	10998000	usd
CY2024Q3	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7728000	usd
CY2024Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	270000	usd
CY2024Q3	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	256000	usd
CY2024Q3	us-gaap	Profit Loss ProfitLoss	-55844000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	763000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.47
CY2024Q3	us-gaap	Dividends Dividends	81547000	usd
CY2024Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	4829000	usd
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3860397000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4544200000	usd
CY2023Q1	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7492000	usd
CY2023Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	287000	usd
CY2023Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q1	us-gaap	Dividends Dividends	107072000	usd
CY2023Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	733000	usd
CY2023Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4560699000	usd
CY2023Q2	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7492000	usd
CY2023Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	235000	usd
CY2023Q2	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	173000	usd
CY2023Q2	us-gaap	Profit Loss ProfitLoss	102497000	usd
CY2023Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	2912000	usd
CY2023Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q2	us-gaap	Dividends Dividends	107028000	usd
CY2023Q2	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	791000	usd
CY2023Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4566189000	usd
CY2023Q3	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Restricted Stock Units Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRestrictedStockUnitsRequisiteServicePeriodRecognition	7434000	usd
CY2023Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	245000	usd
CY2023Q3	bxmt	Adjustments To Additional Paid In Capital Deferred Compensation AdjustmentsToAdditionalPaidInCapitalDeferredCompensation	172000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	30560000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-134000	usd
CY2023Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2023Q3	us-gaap	Dividends Dividends	107033000	usd
CY2023Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	3912000	usd
CY2023Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4493521000	usd
	us-gaap	Profit Loss ProfitLoss	-239216000	usd
	us-gaap	Profit Loss ProfitLoss	251613000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	24058000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	22926000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	50568000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	60333000	usd
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	32185000	usd
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	42620000	usd
	bxmt	Payment In Kind Interest Net Of Interest Received PaymentInKindInterestNetOfInterestReceived	9612000	usd
	bxmt	Payment In Kind Interest Net Of Interest Received PaymentInKindInterestNetOfInterestReceived	1372000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	519747000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	134530000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	5352000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4541000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1214000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	0	usd
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	6346000	usd
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-3195000	usd
	bxmt	Realized Gains Losses On Derivative Financial Instruments Net RealizedGainsLossesOnDerivativeFinancialInstrumentsNet	6923000	usd
	bxmt	Realized Gains Losses On Derivative Financial Instruments Net RealizedGainsLossesOnDerivativeFinancialInstrumentsNet	23800000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-52699000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	931000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-29978000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-16226000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	281908000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	347681000	usd
	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	982229000	usd
	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	1065049000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Receivable ProceedsFromSaleAndCollectionOfLoansReceivable	3135968000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Receivable ProceedsFromSaleAndCollectionOfLoansReceivable	2323258000	usd
	bxmt	Proceeds From Loan Origination And Other Loan Receivable Fees ProceedsFromLoanOriginationAndOtherLoanReceivableFees	26140000	usd
	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	140566000	usd
	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	224367000	usd
	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	56767000	usd
	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	40466000	usd
	bxmt	Payments For Collateral Deposit On Derivative Instrument Investing Activities PaymentsForCollateralDepositOnDerivativeInstrumentInvestingActivities	184220000	usd
	bxmt	Payments For Collateral Deposit On Derivative Instrument Investing Activities PaymentsForCollateralDepositOnDerivativeInstrumentInvestingActivities	230620000	usd
	bxmt	Proceeds From Collateral Deposit On Derivative Instrument Investing Activities ProceedsFromCollateralDepositOnDerivativeInstrumentInvestingActivities	238640000	usd
	bxmt	Proceeds From Collateral Deposit On Derivative Instrument Investing Activities ProceedsFromCollateralDepositOnDerivativeInstrumentInvestingActivities	333730000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	2150500000	usd
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	32185000	usd
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	42620000	usd
	bxmt	Payment In Kind Interest Net Of Interest Received PaymentInKindInterestNetOfInterestReceived	9612000	usd
	bxmt	Payment In Kind Interest Net Of Interest Received PaymentInKindInterestNetOfInterestReceived	1372000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Credit Loss Expense Reversal FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal	519747000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	5352000	usd
	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4541000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1214000	usd
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	0	usd
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	6346000	usd
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-3195000	usd
	bxmt	Realized Gains Losses On Derivative Financial Instruments Net RealizedGainsLossesOnDerivativeFinancialInstrumentsNet	23800000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-52699000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-29978000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-16226000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	281908000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	347681000	usd
	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	982229000	usd
	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	1065049000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Receivable ProceedsFromSaleAndCollectionOfLoansReceivable	3135968000	usd
	us-gaap	Proceeds From Sale And Collection Of Loans Receivable ProceedsFromSaleAndCollectionOfLoansReceivable	2323258000	usd
	bxmt	Proceeds From Loan Origination And Other Loan Receivable Fees ProceedsFromLoanOriginationAndOtherLoanReceivableFees	26140000	usd
	bxmt	Proceeds From Loan Origination And Other Loan Receivable Fees ProceedsFromLoanOriginationAndOtherLoanReceivableFees	11046000	usd
	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	140566000	usd
	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	224367000	usd
	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	56767000	usd
	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	40466000	usd
	bxmt	Payments For Collateral Deposit On Derivative Instrument Investing Activities PaymentsForCollateralDepositOnDerivativeInstrumentInvestingActivities	184220000	usd
	bxmt	Payments For Collateral Deposit On Derivative Instrument Investing Activities PaymentsForCollateralDepositOnDerivativeInstrumentInvestingActivities	230620000	usd
	bxmt	Proceeds From Collateral Deposit On Derivative Instrument Investing Activities ProceedsFromCollateralDepositOnDerivativeInstrumentInvestingActivities	238640000	usd
	bxmt	Proceeds From Collateral Deposit On Derivative Instrument Investing Activities ProceedsFromCollateralDepositOnDerivativeInstrumentInvestingActivities	333730000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	2150500000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1188464000	usd
	bxmt	Proceeds From Sale Of Loan Participations ProceedsFromSaleOfLoanParticipations	0	usd
	bxmt	Proceeds From Sale Of Loan Participations ProceedsFromSaleOfLoanParticipations	50692000	usd
	bxmt	Repayments Of Loan Participations RepaymentsOfLoanParticipations	235960000	usd
	bxmt	Repayments Of Loan Participations RepaymentsOfLoanParticipations	0	usd
	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	18126000	usd
	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	18680000	usd
	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	1245000	usd
	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	usd
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	7296000	usd
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	5436000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	322712000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	320104000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10998000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2458947000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1407463000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-26539000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	128682000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	291340000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-1371000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1473000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	322104000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1188464000	usd
	bxmt	Proceeds From Sale Of Loan Participations ProceedsFromSaleOfLoanParticipations	0	usd
	bxmt	Proceeds From Sale Of Loan Participations ProceedsFromSaleOfLoanParticipations	50692000	usd
	bxmt	Repayments Of Loan Participations RepaymentsOfLoanParticipations	235960000	usd
	bxmt	Repayments Of Loan Participations RepaymentsOfLoanParticipations	0	usd
	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	18126000	usd
	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	18680000	usd
	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	1245000	usd
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	7296000	usd
	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	5436000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	320104000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10998000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2458947000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1407463000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-26539000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	128682000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	350014000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	291340000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-1371000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1473000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	322104000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	421495000	usd
	us-gaap	Interest Paid Net InterestPaidNet	993434000	usd
	us-gaap	Interest Paid Net InterestPaidNet	981945000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	4653000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	5228000	usd
CY2024Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	81306000	usd
CY2023Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	106824000	usd
	bxmt	Loan Principal Payments Held By Servicer LoanPrincipalPaymentsHeldByServicer	26269000	usd
	bxmt	Loan Principal Payments Held By Servicer LoanPrincipalPaymentsHeldByServicer	12713000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	0	usd
	bxmt	Real Estate Owned Assumption Of Other Assets And Liabilities RealEstateOwnedAssumptionOfOtherAssetsAndLiabilities	16256000	usd
	bxmt	Real Estate Owned Assumption Of Other Assets And Liabilities RealEstateOwnedAssumptionOfOtherAssetsAndLiabilities	0	usd
	bxmt	Real Estate Owned Capital Expenditures Incurred But Not Yet Paid RealEstateOwnedCapitalExpendituresIncurredButNotYetPaid	100000	usd
	bxmt	Real Estate Owned Capital Expenditures Incurred But Not Yet Paid RealEstateOwnedCapitalExpendituresIncurredButNotYetPaid	0	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	421495000	usd
	us-gaap	Interest Paid Net InterestPaidNet	993434000	usd
	us-gaap	Interest Paid Net InterestPaidNet	981945000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	4653000	usd
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	5228000	usd
CY2024Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	81306000	usd
CY2023Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	106824000	usd
	bxmt	Loan Principal Payments Held By Servicer LoanPrincipalPaymentsHeldByServicer	26269000	usd
	bxmt	Loan Principal Payments Held By Servicer LoanPrincipalPaymentsHeldByServicer	12713000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	0	usd
	bxmt	Real Estate Owned Assumption Of Other Assets And Liabilities RealEstateOwnedAssumptionOfOtherAssetsAndLiabilities	16256000	usd
	bxmt	Real Estate Owned Assumption Of Other Assets And Liabilities RealEstateOwnedAssumptionOfOtherAssetsAndLiabilities	0	usd
	bxmt	Real Estate Owned Capital Expenditures Incurred But Not Yet Paid RealEstateOwnedCapitalExpendituresIncurredButNotYetPaid	100000	usd
	bxmt	Real Estate Owned Capital Expenditures Incurred But Not Yet Paid RealEstateOwnedCapitalExpendituresIncurredButNotYetPaid	0	usd
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">Certain reclassifications have been made in the presentation of the prior period statement of cash flows related to payment-in-kind interest and principal fundings of loans receivable, in new financings by spread in Note 6, and to the weighted-average maximum maturity of loans receivable in Note 3 to conform to the current period presentation.</span></div>
	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:115%">Use of Estimates</span></div><div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">The preparation of consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may ultimately differ materially from those estimates.</span></div>
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">Certain reclassifications have been made in the presentation of the prior period statement of cash flows related to payment-in-kind interest and principal fundings of loans receivable, in new financings by spread in Note 6, and to the weighted-average maximum maturity of loans receivable in Note 3 to conform to the current period presentation.</span></div>
	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:115%">Use of Estimates</span></div><div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">The preparation of consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may ultimately differ materially from those estimates.</span></div>
	us-gaap	Revenue Recognition Interest RevenueRecognitionInterest	<div style="margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:115%">Revenue Recognition </span></div><div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">Interest income from our loans receivable portfolio is recognized over the life of each loan using the effective interest method and is recorded on the accrual basis. Recognition of fees, premiums, and discounts associated with these investments is deferred and recorded over the term of the loan as an adjustment to yield. Income accrual is generally suspended for loans at the earlier of the date at which payments become 90 days past due or when, in our opinion, recovery of income and principal becomes doubtful. Interest received is then recorded as income or as a reduction in the amortized cost basis, based on the specific facts and circumstances, until accrual is resumed when the loan becomes contractually current and performance is demonstrated to be resumed. In addition, for loans we originate, the related origination expenses are deferred and recognized as a reduction to interest income, however expenses related to loans we acquire are included in general and administrative expenses as incurred.</span></div>
CY2023Q4	us-gaap	Restricted Cash RestrictedCash	0	usd
CY2024Q3	us-gaap	Restricted Cash RestrictedCash	0	usd
CY2024Q3	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Asset FairValueDisclosureOffbalanceSheetRisksAmountAsset	611900000	usd
CY2023Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Asset FairValueDisclosureOffbalanceSheetRisksAmountAsset	640600000	usd
	us-gaap	Revenue Recognition Interest RevenueRecognitionInterest	<div style="margin-top:18pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:115%">Revenue Recognition </span></div><div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">Interest income from our loans receivable portfolio is recognized over the life of each loan using the effective interest method and is recorded on the accrual basis. Recognition of fees, premiums, and discounts associated with these investments is deferred and recorded over the term of the loan as an adjustment to yield. Income accrual is generally suspended for loans at the earlier of the date at which payments become 90 days past due or when, in our opinion, recovery of income and principal becomes doubtful. Interest received is then recorded as income or as a reduction in the amortized cost basis, based on the specific facts and circumstances, until accrual is resumed when the loan becomes contractually current and performance is demonstrated to be resumed. In addition, for loans we originate, the related origination expenses are deferred and recognized as a reduction to interest income, however expenses related to loans we acquire are included in general and administrative expenses as incurred.</span></div>
CY2023Q4	us-gaap	Restricted Cash RestrictedCash	0	usd
CY2024Q3	us-gaap	Restricted Cash RestrictedCash	0	usd
CY2024Q3	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Asset FairValueDisclosureOffbalanceSheetRisksAmountAsset	611900000	usd
CY2023Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Asset FairValueDisclosureOffbalanceSheetRisksAmountAsset	640600000	usd
CY2024Q3	bxmt	Real Estate Owned Number Of Assets Classified As Held For Sale RealEstateOwnedNumberOfAssetsClassifiedAsHeldForSale	3	real_estate_owned_asset
CY2024Q3	bxmt	Real Estate Owned Number Of Assets Classified As Held For Sale RealEstateOwnedNumberOfAssetsClassifiedAsHeldForSale	3	real_estate_owned_asset
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	security_loan
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	security_loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024Q3	us-gaap	Loans Receivable Basis Spread On Variable Rate LoansReceivableBasisSpreadOnVariableRate	0.034
CY2023Q4	us-gaap	Loans Receivable Basis Spread On Variable Rate LoansReceivableBasisSpreadOnVariableRate	0.0337
	bxmt	Financing Receivable Basis Spread On Variable Rate Weighted Average All In Yield FinancingReceivableBasisSpreadOnVariableRateWeightedAverageAllInYield	0.0374
CY2023	bxmt	Financing Receivable Basis Spread On Variable Rate Weighted Average All In Yield FinancingReceivableBasisSpreadOnVariableRateWeightedAverageAllInYield	0.0371
	bxmt	Mortgage Loan On Real Estate Final Maturity Term MortgageLoanOnRealEstateFinalMaturityTerm	P2Y2M12D
CY2023	bxmt	Mortgage Loan On Real Estate Final Maturity Term MortgageLoanOnRealEstateFinalMaturityTerm	P2Y6M
CY2024Q3	bxmt	Financing Receivable Percent Of Loans Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansSubjectToPrepaymentRestrictions	0.14
CY2024Q3	bxmt	Financing Receivable Percent Of Loans Not Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansNotSubjectToPrepaymentRestrictions	0.86
CY2023Q4	bxmt	Financing Receivable Percent Of Loans Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansSubjectToPrepaymentRestrictions	0.14
CY2023Q4	bxmt	Financing Receivable Percent Of Loans Not Subject To Prepayment Restrictions FinancingReceivablePercentOfLoansNotSubjectToPrepaymentRestrictions	0.86
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23923719000	usd
CY2023Q4	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-136707000	usd
	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	982229000	usd
	bxmt	Financing Receivable Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	3055044000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	59848000	usd
	bxmt	Financing Receivable Before Allowance For Credit Loss Fee And Loan In Process Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableBeforeAllowanceForCreditLossFeeAndLoanInProcessSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	3114892000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process Writeoff FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcessWriteoff	104157000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Writeoff FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountWriteoff	13618000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossWriteoff	90539000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Transfer To Other Assets FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossTransferToOtherAssets	30177000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Transfer To Other Assets FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossTransferToOtherAssets	30177000	usd
	us-gaap	Paid In Kind Interest PaidInKindInterest	9612000	usd
	us-gaap	Paid In Kind Interest PaidInKindInterest	9612000	usd
	bxmt	Financing Receivable Gain Loss On Foreign Currency Translation FinancingReceivableGainLossOnForeignCurrencyTranslation	174741000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Unrealized Gain Loss On Foreign Currency Translation FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountUnrealizedGainLossOnForeignCurrencyTranslation	658000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Unrealized Gain Loss On Foreign Currency Translation FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossUnrealizedGainLossOnForeignCurrencyTranslation	174083000	usd
	bxmt	Financing Receivable Deferred Fees And Other Items Increase Decrease FinancingReceivableDeferredFeesAndOtherItemsIncreaseDecrease	26140000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2024Q3	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-159167000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	22428415000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	19346909000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	22428415000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	19346909000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21800000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	99000000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	982229000	usd
	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	982229000	usd
	bxmt	Financing Receivable Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	3055044000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	59848000	usd
	bxmt	Financing Receivable Before Allowance For Credit Loss Fee And Loan In Process Sale And Collection Of Finance Receivables And Cost Recovery Proceeds FinancingReceivableBeforeAllowanceForCreditLossFeeAndLoanInProcessSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceeds	3114892000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process Writeoff FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcessWriteoff	104157000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Writeoff FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountWriteoff	13618000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossWriteoff	90539000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	139239000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Transfer To Other Assets FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossTransferToOtherAssets	30177000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Transfer To Other Assets FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossTransferToOtherAssets	30177000	usd
	us-gaap	Paid In Kind Interest PaidInKindInterest	9612000	usd
	us-gaap	Paid In Kind Interest PaidInKindInterest	9612000	usd
	bxmt	Financing Receivable Gain Loss On Foreign Currency Translation FinancingReceivableGainLossOnForeignCurrencyTranslation	174741000	usd
	bxmt	Financing Receivable Unamortized Loan Fee Cost And Purchase Premium Discount Unrealized Gain Loss On Foreign Currency Translation FinancingReceivableUnamortizedLoanFeeCostAndPurchasePremiumDiscountUnrealizedGainLossOnForeignCurrencyTranslation	658000	usd
	bxmt	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Unrealized Gain Loss On Foreign Currency Translation FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossUnrealizedGainLossOnForeignCurrencyTranslation	174083000	usd
	bxmt	Financing Receivable Deferred Fees And Other Items Increase Decrease FinancingReceivableDeferredFeesAndOtherItemsIncreaseDecrease	26140000	usd
	bxmt	Financing Receivable Deferred Fees And Other Items Increase Decrease FinancingReceivableDeferredFeesAndOtherItemsIncreaseDecrease	26140000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	50568000	usd
	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	50568000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2024Q3	us-gaap	Financing Receivable Unamortized Loan Commitment Origination Fee And Premium Discount FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount	-159167000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	loan
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21800000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	99000000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23900000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	53000000.0	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576900000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	53000000.0	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576900000	usd
	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	149	loan
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	21602517000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	22428415000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	19346909000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21800000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23900000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	99000000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	53000000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576900000	usd
CY2024Q3	bxmt	Financing Receivable Weighted Average Risk Rating FinancingReceivableWeightedAverageRiskRating	3.1
CY2023Q4	bxmt	Financing Receivable Weighted Average Risk Rating FinancingReceivableWeightedAverageRiskRating	3.0
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2024Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	235447000	usd
CY2024Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	61013000	usd
CY2024Q1	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	751370000	usd
CY2024Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	155105000	usd
CY2024Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	12537000	usd
CY2024Q2	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	893938000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	134110000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	16989000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	326137000	usd
CY2023Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	10454000	usd
CY2023Q1	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	336591000	usd
CY2023Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	27284000	usd
CY2023Q2	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	363875000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	99548000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	463423000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Period Increase Decrease And Writeoff Net FinancingReceivableExcludingAccruedInterestPeriodIncreaseDecreaseAndWriteoffNet	117100000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	134100000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2024Q3	bxmt	Financing Receivable Number Of Impaired Loans Resolved During The Period FinancingReceivableNumberOfImpairedLoansResolvedDuringThePeriod	1	loan
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	22428415000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	19346909000	usd
CY2023	bxmt	Financing Receivable Number Of Loans FinancingReceivableNumberOfLoans	178	loan
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	23787012000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Loan Exposure FinancingReceivableExcludingAccruedInterestLoanExposure	24971028000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Net Loans Exposure Amount FinancingReceivableExcludingAccruedInterestNetLoansExposureAmount	21951988000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21800000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23900000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	99000000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2023Q4	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	1100000000	usd
CY2023Q4	bxmt	Financing Receivable Excluding Accrued Interest Unamortized Loan Fee Cost And Purchase Premium Discount Sale And Collection Of Finance Receivables And Cost Recovery Proceeds Net FinancingReceivableExcludingAccruedInterestUnamortizedLoanFeeCostAndPurchasePremiumDiscountSaleAndCollectionOfFinanceReceivablesAndCostRecoveryProceedsNet	53000000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576900000	usd
CY2024Q3	bxmt	Financing Receivable Weighted Average Risk Rating FinancingReceivableWeightedAverageRiskRating	3.1
CY2023Q4	bxmt	Financing Receivable Weighted Average Risk Rating FinancingReceivableWeightedAverageRiskRating	3.0
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2024Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	235447000	usd
CY2024Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	61013000	usd
CY2024Q1	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	751370000	usd
CY2024Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	155105000	usd
CY2024Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	12537000	usd
CY2024Q2	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	893938000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	16989000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	326137000	usd
CY2023Q1	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	10454000	usd
CY2023Q1	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	336591000	usd
CY2023Q2	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	27284000	usd
CY2023Q2	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	363875000	usd
CY2023Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	99548000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	463423000	usd
CY2024Q3	bxmt	Financing Receivable Excluding Accrued Interest Period Increase Decrease And Writeoff Net FinancingReceivableExcludingAccruedInterestPeriodIncreaseDecreaseAndWriteoffNet	117100000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Period Increase Decrease FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease	134100000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1000000000	usd
CY2024Q3	bxmt	Financing Receivable Number Of Impaired Loans Resolved During The Period FinancingReceivableNumberOfImpairedLoansResolvedDuringThePeriod	1	loan
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	17450000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	53587000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	19502000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	90539000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024	bxmt	Financing Receivable Modified Number Of Contracts FinancingReceivableModifiedNumberOfContracts	6	loan
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	1011059000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	17450000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	53587000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	0	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	19502000	usd
	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	90539000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	576936000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2024	bxmt	Financing Receivable Modified Number Of Contracts FinancingReceivableModifiedNumberOfContracts	6	loan
	bxmt	Real Estate Owned Number Of Assets RealEstateOwnedNumberOfAssets	3	real_estate_owned_asset
	bxmt	Real Estate Owned Consideration Transferred RealEstateOwnedConsiderationTransferred	159900000	usd
CY2024Q3	bxmt	Building And Building Improvements Acquired Through Foreclosure Purchase Price Allocation BuildingAndBuildingImprovementsAcquiredThroughForeclosurePurchasePriceAllocation	75700000	usd
CY2024Q3	bxmt	Land And Site Improvements Acquired Through Foreclosure Purchase Price Allocation LandAndSiteImprovementsAcquiredThroughForeclosurePurchasePriceAllocation	63500000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Gross Purchase Price Allocation IntangibleRealEstateAcquiredThroughForeclosureGrossPurchasePriceAllocation	19200000	usd
CY2024Q3	bxmt	Other Assets Acquired Through Foreclosure Purchase Price Allocation OtherAssetsAcquiredThroughForeclosurePurchasePriceAllocation	1500000	usd
CY2023Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	0	usd
CY2024Q1	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	60200000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	33600000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	64600000	usd
CY2024Q3	bxmt	Land And Site Improvements Acquired Through Foreclosure LandAndSiteImprovementsAcquiredThroughForeclosure	63494000	usd
CY2024Q3	bxmt	Building And Building Improvements Acquired Through Foreclosure BuildingAndBuildingImprovementsAcquiredThroughForeclosure	75847000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	139341000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Accumulated Depreciation RealEstateAcquiredThroughForeclosureAccumulatedDepreciation	616000	usd
CY2024Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	138725000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Gross IntangibleRealEstateAcquiredThroughForeclosureGross	19200000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Accumulated Depreciation IntangibleRealEstateAcquiredThroughForeclosureAccumulatedDepreciation	598000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	18602000	usd
CY2024Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1200000	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1200000	usd
CY2024Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	2700000	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	3600000	usd
CY2024Q3	bxmt	Real Estate Owned Depreciation And Amortization Expense RealEstateOwnedDepreciationAndAmortizationExpense	1000000.0	usd
	bxmt	Real Estate Owned Depreciation And Amortization Expense RealEstateOwnedDepreciationAndAmortizationExpense	1200000	usd
CY2024Q3	bxmt	Real Estate Owned Operating Expenses RealEstateOwnedOperatingExpenses	1700000	usd
	bxmt	Real Estate Owned Operating Expenses RealEstateOwnedOperatingExpenses	2400000	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
CY2023Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
CY2023Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
	bxmt	Real Estate Owned Number Of Assets RealEstateOwnedNumberOfAssets	3	real_estate_owned_asset
	bxmt	Real Estate Owned Consideration Transferred RealEstateOwnedConsiderationTransferred	159900000	usd
CY2024Q3	bxmt	Building And Building Improvements Acquired Through Foreclosure Purchase Price Allocation BuildingAndBuildingImprovementsAcquiredThroughForeclosurePurchasePriceAllocation	75700000	usd
CY2024Q3	bxmt	Land And Site Improvements Acquired Through Foreclosure Purchase Price Allocation LandAndSiteImprovementsAcquiredThroughForeclosurePurchasePriceAllocation	63500000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Gross Purchase Price Allocation IntangibleRealEstateAcquiredThroughForeclosureGrossPurchasePriceAllocation	19200000	usd
CY2024Q3	bxmt	Other Assets Acquired Through Foreclosure Purchase Price Allocation OtherAssetsAcquiredThroughForeclosurePurchasePriceAllocation	1500000	usd
CY2023Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	0	usd
CY2024Q1	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	60200000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	33600000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	64600000	usd
CY2024Q3	bxmt	Land And Site Improvements Acquired Through Foreclosure LandAndSiteImprovementsAcquiredThroughForeclosure	63494000	usd
CY2024Q3	bxmt	Building And Building Improvements Acquired Through Foreclosure BuildingAndBuildingImprovementsAcquiredThroughForeclosure	75847000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Gross RealEstateAcquiredThroughForeclosureGross	139341000	usd
CY2024Q3	bxmt	Real Estate Acquired Through Foreclosure Accumulated Depreciation RealEstateAcquiredThroughForeclosureAccumulatedDepreciation	616000	usd
CY2024Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	138725000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Gross IntangibleRealEstateAcquiredThroughForeclosureGross	19200000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Accumulated Depreciation IntangibleRealEstateAcquiredThroughForeclosureAccumulatedDepreciation	598000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	18602000	usd
CY2024Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1200000	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	1200000	usd
CY2024Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	2700000	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	3600000	usd
CY2024Q3	bxmt	Real Estate Owned Depreciation And Amortization Expense RealEstateOwnedDepreciationAndAmortizationExpense	1000000.0	usd
	bxmt	Real Estate Owned Depreciation And Amortization Expense RealEstateOwnedDepreciationAndAmortizationExpense	1200000	usd
	bxmt	Real Estate Owned Operating Expenses RealEstateOwnedOperatingExpenses	2400000	usd
	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
CY2023Q3	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
CY2023Q3	bxmt	Real Estate Owned Income RealEstateOwnedIncome	0	usd
	bxmt	Real Estate Owned Expenses RealEstateOwnedExpenses	0	usd
CY2024Q3	us-gaap	Interest Receivable InterestReceivable	176049000	usd
CY2023Q4	us-gaap	Interest Receivable InterestReceivable	214835000	usd
CY2024Q3	us-gaap	Interest Receivable InterestReceivable	176049000	usd
CY2023Q4	us-gaap	Interest Receivable InterestReceivable	214835000	usd
CY2024Q3	bxmt	Loan Portfolio Payments Held By Our Third Party Loan Servicer LoanPortfolioPaymentsHeldByOurThirdPartyLoanServicer	131347000	usd
CY2023Q4	bxmt	Loan Portfolio Payments Held By Our Third Party Loan Servicer LoanPortfolioPaymentsHeldByOurThirdPartyLoanServicer	152423000	usd
CY2024Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	49080000	usd
CY2023Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	103500000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	18602000	usd
CY2023Q4	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	0	usd
CY2024Q3	bxmt	Accounts Receivable Net Current And Other Assets Current AccountsReceivableNetCurrentAndOtherAssetsCurrent	8157000	usd
CY2023Q4	bxmt	Accounts Receivable Net Current And Other Assets Current AccountsReceivableNetCurrentAndOtherAssetsCurrent	2420000	usd
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	7026000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	646000	usd
CY2023Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	1020000	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	390907000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	476088000	usd
CY2024Q3	bxmt	Secured Debt Repayments Pending Servicer Remittance SecuredDebtRepaymentsPendingServicerRemittance	105078000	usd
CY2023Q4	bxmt	Secured Debt Repayments Pending Servicer Remittance SecuredDebtRepaymentsPendingServicerRemittance	13526000	usd
CY2024Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	81306000	usd
CY2024Q3	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	74168000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
CY2024Q3	bxmt	Management And Incentive Fee Payable ManagementAndIncentiveFeePayable	18605000	usd
CY2023Q4	bxmt	Management And Incentive Fee Payable ManagementAndIncentiveFeePayable	26342000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	8307000	usd
CY2023Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	15371000	usd
CY2024Q3	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	8662000	usd
CY2023Q4	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	7265000	usd
CY2024Q3	us-gaap	Other Liabilities OtherLiabilities	346382000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	362531000	usd
CY2024Q3	bxmt	Loan Portfolio Payments Held By Our Third Party Loan Servicer LoanPortfolioPaymentsHeldByOurThirdPartyLoanServicer	131347000	usd
CY2023Q4	bxmt	Loan Portfolio Payments Held By Our Third Party Loan Servicer LoanPortfolioPaymentsHeldByOurThirdPartyLoanServicer	152423000	usd
CY2024Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	49080000	usd
CY2023Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	103500000	usd
CY2024Q3	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	18602000	usd
CY2023Q4	bxmt	Intangible Real Estate Acquired Through Foreclosure Net IntangibleRealEstateAcquiredThroughForeclosureNet	0	usd
CY2024Q3	bxmt	Accounts Receivable Net Current And Other Assets Current AccountsReceivableNetCurrentAndOtherAssetsCurrent	8157000	usd
CY2023Q4	bxmt	Accounts Receivable Net Current And Other Assets Current AccountsReceivableNetCurrentAndOtherAssetsCurrent	2420000	usd
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	7026000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	646000	usd
CY2023Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	1020000	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	390907000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	476088000	usd
CY2024Q3	bxmt	Secured Debt Repayments Pending Servicer Remittance SecuredDebtRepaymentsPendingServicerRemittance	105078000	usd
CY2023Q4	bxmt	Secured Debt Repayments Pending Servicer Remittance SecuredDebtRepaymentsPendingServicerRemittance	13526000	usd
CY2024Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	81306000	usd
CY2023Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	107390000	usd
CY2024Q3	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	74168000	usd
CY2023Q4	us-gaap	Interest Payable Current And Noncurrent InterestPayableCurrentAndNoncurrent	97820000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	50256000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	8307000	usd
CY2023Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	15371000	usd
CY2024Q3	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	8662000	usd
CY2023Q4	us-gaap	Accounts Payable And Other Accrued Liabilities AccountsPayableAndOtherAccruedLiabilities	7265000	usd
CY2024Q3	us-gaap	Other Liabilities OtherLiabilities	346382000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	362531000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-1600000	usd
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-7100000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	8300000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	2600000	usd
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-2800000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	13600000	usd
CY2023Q4	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	337721000	usd
CY2023Q4	bxmt	Loan Participations Sold Liabilities Amount LoanParticipationsSoldLiabilitiesAmount	337179000	usd
CY2024Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-1600000	usd
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-7100000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	2600000	usd
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-2800000	usd
CY2023Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	13600000	usd
CY2023Q4	bxmt	Loan Participations Sold Total Loan LoanParticipationsSoldTotalLoan	697565000	usd
CY2023Q4	bxmt	Loan Participations Sold Total Loan Amount LoanParticipationsSoldTotalLoanAmount	694386000	usd
CY2024Q3	us-gaap	Share Price SharePrice	19.01
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	65000	usd
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	7026000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	50256000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	-47120000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	usd
	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-81000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	993000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	399000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	1245000	usd
	bxmt	Other Comprehensive Income Loss Net Investment Hedge And Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeAndCashFlowHedgeGainLossBeforeReclassificationAndTax	-46127000	usd
CY2024Q3	bxmt	Other Comprehensive Income Loss Cash Flow And Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowAndNetInvestmentHedgeGainLossReclassificationBeforeTax	399000	usd
	bxmt	Other Comprehensive Income Loss Cash Flow And Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowAndNetInvestmentHedgeGainLossReclassificationBeforeTax	1245000	usd
CY2024Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	321700000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	1000000000	usd
CY2024Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	49100000	usd
CY2023Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	103500000	usd
CY2023Q4	bxmt	Common And Preferred Stock Shares Authorized CommonAndPreferredStockSharesAuthorized	500000000	shares
CY2024Q3	bxmt	Common And Preferred Stock Shares Authorized CommonAndPreferredStockSharesAuthorized	500000000	shares
CY2024Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2023Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2024Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2023Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2023Q4	bxmt	Loan Participations Sold Total Loan LoanParticipationsSoldTotalLoan	697565000	usd
CY2023Q4	bxmt	Loan Participations Sold Total Loan Amount LoanParticipationsSoldTotalLoanAmount	694386000	usd
CY2024Q3	us-gaap	Share Price SharePrice	19.01
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	65000	usd
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	7026000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	50256000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	-89829000	usd
	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	-47120000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	399000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	1245000	usd
CY2024Q3	bxmt	Other Comprehensive Income Loss Net Investment Hedge And Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeAndCashFlowHedgeGainLossBeforeReclassificationAndTax	-89910000	usd
	bxmt	Other Comprehensive Income Loss Net Investment Hedge And Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeAndCashFlowHedgeGainLossBeforeReclassificationAndTax	-46127000	usd
CY2024Q3	bxmt	Other Comprehensive Income Loss Cash Flow And Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowAndNetInvestmentHedgeGainLossReclassificationBeforeTax	399000	usd
	bxmt	Other Comprehensive Income Loss Cash Flow And Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowAndNetInvestmentHedgeGainLossReclassificationBeforeTax	1245000	usd
CY2024Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	321700000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	1000000000	usd
CY2024Q3	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	49100000	usd
CY2023Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	103500000	usd
CY2023Q4	bxmt	Common And Preferred Stock Shares Authorized CommonAndPreferredStockSharesAuthorized	500000000	shares
CY2024Q3	bxmt	Common And Preferred Stock Shares Authorized CommonAndPreferredStockSharesAuthorized	500000000	shares
CY2024Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	400000000	shares
CY2023Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2024Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	100000000	shares
CY2023Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2023Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2024Q3	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2024Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2024Q3	srt	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	150000000.0	usd
CY2024Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	628884	shares
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Per Share Weighted Average Price Of Shares Purchased ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased	17.49
CY2024Q3	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	11000000.0	usd
CY2023Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
CY2024Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	139000000.0	usd
CY2023Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2024Q3	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2024Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	628884	shares
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CY2023Q3	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
CY2024Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	139000000.0	usd
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CY2022Q4	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	172106593	shares
	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	4647	shares
	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	5079	shares
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	628884	shares
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	bxmt	Stock Issued During Period Shares Deferred Stock Units StockIssuedDuringPeriodSharesDeferredStockUnits	43656	shares
CY2024Q3	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	173389399	shares
CY2023Q3	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	172645283	shares
	us-gaap	Stock Issued During Period Shares Restricted Stock Award Forfeited StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited	102484	shares
	us-gaap	Stock Issued During Period Shares Restricted Stock Award Forfeited StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited	15477	shares
CY2024Q3	bxmt	Dividend Reinvestment And Direct Stock Purchase Plan Shares Authorized DividendReinvestmentAndDirectStockPurchasePlanSharesAuthorized	10000000	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	4647	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	5079	shares
CY2024Q3	bxmt	Dividend Reinvestment And Direct Stock Purchase Plan Remaining Shares Available For Future Issuance DividendReinvestmentAndDirectStockPurchasePlanRemainingSharesAvailableForFutureIssuance	9970314	shares
	bxmt	Sale Of Stock Number Of Equity Distribution Agreements SaleOfStockNumberOfEquityDistributionAgreements	7	agreement
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	us-gaap	Sale Of Stock Number Of Shares Issued In Transaction SaleOfStockNumberOfSharesIssuedInTransaction	0	shares
CY2024Q3	bxmt	Sale Of Stock Remaining Authorized Amount SaleOfStockRemainingAuthorizedAmount	480900000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.47
CY2023Q4	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	173569397	shares
CY2022Q4	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	172106593	shares
	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	4647	shares
	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	5079	shares
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	us-gaap	Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures	489955	shares
	bxmt	Stock Issued During Period Shares Deferred Stock Units StockIssuedDuringPeriodSharesDeferredStockUnits	42338	shares
	bxmt	Stock Issued During Period Shares Deferred Stock Units StockIssuedDuringPeriodSharesDeferredStockUnits	43656	shares
CY2024Q3	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	173389399	shares
CY2023Q3	bxmt	Common Stock Shares Outstanding Including Deferred Stock Units CommonStockSharesOutstandingIncludingDeferredStockUnits	172645283	shares
	us-gaap	Stock Issued During Period Shares Restricted Stock Award Forfeited StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited	102484	shares
	us-gaap	Stock Issued During Period Shares Restricted Stock Award Forfeited StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited	15477	shares
CY2024Q3	bxmt	Dividend Reinvestment And Direct Stock Purchase Plan Shares Authorized DividendReinvestmentAndDirectStockPurchasePlanSharesAuthorized	10000000	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	4647	shares
	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	5079	shares
CY2024Q3	bxmt	Dividend Reinvestment And Direct Stock Purchase Plan Remaining Shares Available For Future Issuance DividendReinvestmentAndDirectStockPurchasePlanRemainingSharesAvailableForFutureIssuance	9970314	shares
	bxmt	Sale Of Stock Number Of Equity Distribution Agreements SaleOfStockNumberOfEquityDistributionAgreements	7	agreement
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CY2024Q3	bxmt	Sale Of Stock Remaining Authorized Amount SaleOfStockRemainingAuthorizedAmount	480900000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.47
CY2024Q3	us-gaap	Dividends Common Stock DividendsCommonStock	81300000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.47
CY2023Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.71
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CY2024Q3	us-gaap	Dividends Common Stock DividendsCommonStock	81306000	usd
CY2023Q3	us-gaap	Dividends Common Stock DividendsCommonStock	106824000	usd
	us-gaap	Dividends Common Stock DividendsCommonStock	296624000	usd
CY2023Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2024Q3	us-gaap	Dividends Common Stock DividendsCommonStock	81306000	usd
CY2023Q3	us-gaap	Dividends Common Stock DividendsCommonStock	106824000	usd
	us-gaap	Dividends Common Stock DividendsCommonStock	296624000	usd
	us-gaap	Dividends Common Stock DividendsCommonStock	320471000	usd
CY2024Q3	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	241000	usd
CY2023Q3	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	209000	usd
	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	694000	usd
	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	662000	usd
CY2024Q3	us-gaap	Dividends Dividends	81547000	usd
CY2023Q3	us-gaap	Dividends Dividends	107033000	usd
	us-gaap	Dividends Dividends	297318000	usd
	us-gaap	Dividends Dividends	321133000	usd
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	248932000	usd
CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173637101	shares
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172648118	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173881116	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172620799	shares
CY2024Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.32
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.17
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	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.44
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	248932000	usd
CY2024Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	0	usd
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CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	259599000	usd
CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173637101	shares
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172648118	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173881116	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172620799	shares
CY2024Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2023Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	8271060	shares
CY2024Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	173637101	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172648118	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	173881116	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	180891859	shares
CY2024Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.32
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CY2023Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
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CY2024Q3	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	241000	usd
CY2023Q3	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	209000	usd
	us-gaap	Dividends Share Based Compensation DividendsShareBasedCompensation	694000	usd
CY2023Q3	us-gaap	Dividends Dividends	107033000	usd
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	248932000	usd
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172648118	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173881116	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172620799	shares
CY2024Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.32
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.17
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CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	248932000	usd
CY2024Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	0	usd
CY2023Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	0	usd
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	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	10667000	usd
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-56384000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	29524000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-241279000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	259599000	usd
CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173637101	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	173881116	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	172620799	shares
CY2024Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2023Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	8271060	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	172648118	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	173881116	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	180891859	shares
CY2024Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.32
CY2023Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.17
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.39
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2023Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2024Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	8300000	shares
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	11100000	usd
CY2024Q3	us-gaap	Aoci Loss Cash Flow Hedge Cumulative Gain Loss After Tax AociLossCashFlowHedgeCumulativeGainLossAfterTax	136500000	usd
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-125400000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	9500000	usd
CY2023Q4	us-gaap	Aoci Loss Cash Flow Hedge Cumulative Gain Loss After Tax AociLossCashFlowHedgeCumulativeGainLossAfterTax	183900000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-174400000	usd
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CY2024Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
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CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	11100000	usd
CY2024Q3	us-gaap	Aoci Loss Cash Flow Hedge Cumulative Gain Loss After Tax AociLossCashFlowHedgeCumulativeGainLossAfterTax	136500000	usd
CY2024Q3	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-125400000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	9500000	usd
CY2023Q4	us-gaap	Aoci Loss Cash Flow Hedge Cumulative Gain Loss After Tax AociLossCashFlowHedgeCumulativeGainLossAfterTax	183900000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-174400000	usd
	us-gaap	Management And Service Fees Rate ManagementAndServiceFeesRate	0.0150
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CY2024Q3	bxmt	Accrued Management And Incentive Fees Payable AccruedManagementAndIncentiveFeesPayable	18600000	usd
CY2023Q4	bxmt	Accrued Management And Incentive Fees Payable AccruedManagementAndIncentiveFeesPayable	26300000	usd
CY2023Q3	us-gaap	Professional Fees ProfessionalFees	3038000	usd
	us-gaap	Professional Fees ProfessionalFees	11709000	usd
	us-gaap	Professional Fees ProfessionalFees	9579000	usd
CY2024Q3	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	1686000	usd
CY2023Q3	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	1357000	usd
	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	5044000	usd
	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	5383000	usd
CY2024Q3	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	5439000	usd
CY2023Q3	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	4395000	usd
	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	16753000	usd
	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	14962000	usd
CY2024Q3	us-gaap	Restricted Stock Expense RestrictedStockExpense	7728000	usd
CY2023Q3	us-gaap	Restricted Stock Expense RestrictedStockExpense	7434000	usd
	us-gaap	Restricted Stock Expense RestrictedStockExpense	23400000	usd
	us-gaap	Restricted Stock Expense RestrictedStockExpense	22418000	usd
CY2024Q3	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	256000	usd
CY2023Q3	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	172000	usd
	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	658000	usd
	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	508000	usd
CY2024Q3	us-gaap	Share Based Compensation ShareBasedCompensation	7984000	usd
CY2023Q3	us-gaap	Share Based Compensation ShareBasedCompensation	7606000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	24058000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	22926000	usd
CY2024Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	13423000	usd
CY2023Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	12001000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	40811000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	37888000	usd
CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	613000	usd
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CY2023Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1600000	usd
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CY2013Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	25875000	shares
CY2013Q2	bxmt	Operating Loss Carryforwards Limitations On Use Annual Limitation OperatingLossCarryforwardsLimitationsOnUseAnnualLimitation	2000000.0	usd
CY2024Q3	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	159000000.0	usd
CY2024Q3	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfStockIncentivePlans	2	plan
CY2022Q2	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfStockIncentivePlans	9	plan
CY2022Q2	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Retired Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfRetiredStockIncentivePlans	7	plan
	us-gaap	Management And Service Fees Incentive Rate ManagementAndServiceFeesIncentiveRate	0.20
CY2024Q3	bxmt	Management Fee Core Earnings Fee Percentage ManagementFeeCoreEarningsFeePercentage	0.0700
	bxmt	Management Fee Core Earnings Measurement Period ManagementFeeCoreEarningsMeasurementPeriod	P3Y
	bxmt	Management Fee Core Earnings Minimum Threshold ManagementFeeCoreEarningsMinimumThreshold	0
CY2024Q3	bxmt	Accrued Management And Incentive Fees Payable AccruedManagementAndIncentiveFeesPayable	18600000	usd
CY2023Q4	bxmt	Accrued Management And Incentive Fees Payable AccruedManagementAndIncentiveFeesPayable	26300000	usd
CY2024Q3	us-gaap	Professional Fees ProfessionalFees	3753000	usd
CY2023Q3	us-gaap	Professional Fees ProfessionalFees	3038000	usd
	us-gaap	Professional Fees ProfessionalFees	11709000	usd
	us-gaap	Professional Fees ProfessionalFees	9579000	usd
CY2024Q3	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	1686000	usd
CY2023Q3	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	1357000	usd
	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	5044000	usd
	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	5383000	usd
CY2024Q3	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	5439000	usd
CY2023Q3	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	4395000	usd
	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	16753000	usd
	bxmt	General And Administrative Expense Excluding Non Cash Compensation Expense GeneralAndAdministrativeExpenseExcludingNonCashCompensationExpense	14962000	usd
CY2024Q3	us-gaap	Restricted Stock Expense RestrictedStockExpense	7728000	usd
CY2023Q3	us-gaap	Restricted Stock Expense RestrictedStockExpense	7434000	usd
	us-gaap	Restricted Stock Expense RestrictedStockExpense	23400000	usd
	us-gaap	Restricted Stock Expense RestrictedStockExpense	22418000	usd
CY2024Q3	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	256000	usd
CY2023Q3	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	172000	usd
	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	658000	usd
	bxmt	Director Share Based Payment Arrangement Expense DirectorShareBasedPaymentArrangementExpense	508000	usd
CY2024Q3	us-gaap	Share Based Compensation ShareBasedCompensation	7984000	usd
CY2023Q3	us-gaap	Share Based Compensation ShareBasedCompensation	7606000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	24058000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	22926000	usd
CY2023Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	12001000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	40811000	usd
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	37888000	usd
CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	613000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2800000	usd
CY2023Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1600000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4700000	usd
CY2013Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	25875000	shares
CY2013Q2	bxmt	Operating Loss Carryforwards Limitations On Use Annual Limitation OperatingLossCarryforwardsLimitationsOnUseAnnualLimitation	2000000.0	usd
CY2024Q3	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	159000000.0	usd
CY2024Q3	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfStockIncentivePlans	2	plan
CY2022Q2	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfStockIncentivePlans	9	plan
CY2022Q2	bxmt	Share Based Compensation Arrangement By Share Based Payment Award Number Of Retired Stock Incentive Plans ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfRetiredStockIncentivePlans	7	plan
CY2024Q3	us-gaap	Derivative Assets DerivativeAssets	7026000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	50256000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
CY2024Q3	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	322104000	usd
CY2024Q3	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	322104000	usd
CY2024Q3	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	322104000	usd
CY2023Q4	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	350014000	usd
CY2023Q4	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	350014000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	350014000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	20591458000	usd
CY2024Q3	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	21761684000	usd
CY2024Q3	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	20480151000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23923719000	usd
CY2023Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	23015737000	usd
CY2024Q3	bxmt	Loan Participations Sold Liabilities Amount LoanParticipationsSoldLiabilitiesAmount	103489000	usd
CY2024Q3	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	103500000	usd
CY2023Q4	bxmt	Loan Participations Sold Liabilities Fair Value LoanParticipationsSoldLiabilitiesFairValue	333745000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	1890000	usd
CY2024Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	50256000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	94817000	usd
CY2024Q3	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	322104000	usd
CY2024Q3	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	322104000	usd
CY2024Q3	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	322104000	usd
CY2023Q4	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	350014000	usd
CY2023Q4	bxmt	Cash And Cash Equivalents CashAndCashEquivalents	350014000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	350014000	usd
CY2024Q3	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	20480151000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest After Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss	23210076000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss Fee And Loan In Process FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess	23923719000	usd
CY2023Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	23015737000	usd
CY2024Q3	bxmt	Loan Participations Sold Liabilities Amount LoanParticipationsSoldLiabilitiesAmount	103489000	usd
CY2024Q3	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	103500000	usd
CY2024Q3	bxmt	Loan Participations Sold Liabilities Fair Value LoanParticipationsSoldLiabilitiesFairValue	103114000	usd
CY2023Q4	bxmt	Loan Participations Sold Liabilities Amount LoanParticipationsSoldLiabilitiesAmount	337179000	usd
CY2023Q4	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	337721000	usd
CY2023Q4	bxmt	Loan Participations Sold Liabilities Fair Value LoanParticipationsSoldLiabilitiesFairValue	333745000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	317887000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	2378609000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	5184971000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	4611317000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	537754000	usd
CY2024Q3	bxmt	Long Term Debt Maturity After Year Four LongTermDebtMaturityAfterYearFour	1901155000	usd
CY2024Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	14931693000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	317887000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	2378609000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	5184971000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	4611317000	usd
CY2024Q3	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	537754000	usd
CY2024Q3	bxmt	Long Term Debt Maturity After Year Four LongTermDebtMaturityAfterYearFour	1901155000	usd
CY2024Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	14931693000	usd
CY2024Q3	bxmt	Loan Exposure Amount Including Non Consolidated Senior Interests LoanExposureAmountIncludingNonConsolidatedSeniorInterests	770200000	usd
CY2024Q3	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	103500000	usd
	bxmt	Board Of Directors Number Of Members BoardOfDirectorsNumberOfMembers	9	director
	bxmt	Board Of Directors Number Of Directors Eligible For Compensation BoardOfDirectorsNumberOfDirectorsEligibleForCompensation	7	director
	bxmt	Board Of Directors Number Of Members Not Eligible For Annual Compensation BoardOfDirectorsNumberOfMembersNotEligibleForAnnualCompensation	2	director
CY2024Q3	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2024Q3	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2024Q3	bxmt	Loan Participation Liabilities Principal Amount LoanParticipationLiabilitiesPrincipalAmount	103500000	usd
	bxmt	Board Of Directors Number Of Members BoardOfDirectorsNumberOfMembers	9	director
	bxmt	Board Of Directors Number Of Directors Eligible For Compensation BoardOfDirectorsNumberOfDirectorsEligibleForCompensation	7	director
	bxmt	Board Of Directors Number Of Members Not Eligible For Annual Compensation BoardOfDirectorsNumberOfMembersNotEligibleForAnnualCompensation	2	director
CY2024Q3	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2024Q3	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false

Files In Submission

Name	View Source	Status
0001061630-24-000148-index-headers.html	Edgar Link	pending
0001061630-24-000148-index.html	Edgar Link	pending
0001061630-24-000148.txt	Edgar Link	pending
0001061630-24-000148-xbrl.zip	Edgar Link	pending
bxmt-20240930.htm	Edgar Link	pending
bxmt-20240930.xsd	Edgar Link	pending
bxmt-20240930_g1.gif	Edgar Link	pending
bxmt-20240930_g2.jpg	Edgar Link	pending
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exhibit1013q24.htm	Edgar Link	pending
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exhibit3113q24.htm	Edgar Link	pending
exhibit3123q24.htm	Edgar Link	pending
exhibit3213q24.htm	Edgar Link	pending
exhibit3223q24.htm	Edgar Link	pending
exhibit9913q24.htm	Edgar Link	pending
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
bxmt-20240930_cal.xml	Edgar Link	unprocessable
bxmt-20240930_pre.xml	Edgar Link	unprocessable
FilingSummary.xml	Edgar Link	unprocessable
bxmt-20240930_htm.xml	Edgar Link	completed
bxmt-20240930_lab.xml	Edgar Link	unprocessable
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending
bxmt-20240930_def.xml	Edgar Link	unprocessable

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$BXMT
BLACKSTONE MORTGAGE TRUST, INC. Stock $bxmt

2024 Q4 Form 10-Q Financial Statement

#000106163024000148 Filed on October 23, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BXMT BLACKSTONE MORTGAGE TRUST, INC. Stock $bxmt

2024 Q4 Form 10-Q Financial Statement

#000106163024000148 Filed on October 23, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BXMT
BLACKSTONE MORTGAGE TRUST, INC. Stock $bxmt