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To Total Unsecured Debt Ratio, Minimum Debt Instrument, Covenant, Total Unencumbered Assets To Total Unsecured Debt Ratio, Minimum Termination Date Trading Arrangement Termination Date 7 Real Estate Owned Assets 7 Real Estate Owned Assets [Member] 7 Real Estate Owned Assets Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Insurance costs inclusive of premiums, capital surplus contributions, taxes and pro rata share of expenses Amount Contributed To Captive Towards Insurance Premium Amount Contributed To Captive Towards Insurance Premium Disclosure Details Of Loan Receivable Portfolio Based On Index Floor Rates Disclosure Details Of Loan Receivable Portfolio Based On Floor Rate [Table Text Block] Disclosure Details Of Loan Receivable Portfolio Based On Floor Rate Debt instrument, variable interest rate, type [Extensible Enumeration] Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] Current expected credit loss reserve CECL reserve CECL reserve Beginning balance Ending balance Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest Receivable [Domain] Receivable [Domain] Vest in 2028 Share-Based Payment Arrangement, Tranche Three [Member] Loan participations sold Principal Balance, loan participation Loan participations sold, net, face amount Loan Participation Liabilities, Principal Amount Loan Participation Liabilities, Principal Amount Senior Loans, Blackstone-Advised Investment Vehicle Senior Loans, Blackstone-Advised Investment Vehicle [Member] Senior Loans, Blackstone-Advised Investment Vehicle B-4 Term Loan Due 2029, Repaid With B-6 Term Loan Proceeds B-4 Term Loan Due 2029, Repaid With B-6 Term Loan Proceeds [Member] B-4 Term Loan Due 2029, Repaid With B-6 Term Loan Proceeds Basic (in shares) Weighted-average shares outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Schedule of Basic and Diluted Earnings Per Share, or EPS, Based on Weighted-Average of Both Restricted and Unrestricted Class A Common Stock Outstanding Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Director Director [Member] Segment Reporting [Abstract] Director stock-based compensation Director Share-Based Payment Arrangement, Expense Director Share-Based Payment Arrangement, Expense Payments under derivative financial instruments, net of adjustments Payments for Derivative Instrument, Investing Activities, Net Of Adjustments Payments for Derivative Instrument, Investing Activities, Net Of Adjustments Debt Disclosure [Abstract] Debt Disclosure [Abstract] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Consolidated Entities [Axis] Consolidated Entities [Axis] Derivative Instruments and Hedging Activities Disclosures [Line Items] Derivative Instruments and Hedging Activities Disclosures [Line Items] 1.01% to 2.00% floor Financing Receivable, 1.01% To 2.00% Floor [Member] Financing Receivable, 1.01% To 2.00% Floor Geographic Distribution [Axis] Geographic Distribution [Axis] Use of Estimates Use of Estimates, Policy [Policy Text Block] Net unfunded commitments Off-Balance-Sheet, Credit Loss, Liability, Net Off-Balance-Sheet, Credit Loss, Liability, Net Additional lender funding Secured Credit Facility, Additional Lender Funding [Member] Secured Credit Facility, Additional Lender Funding Insider Trading Arrangements [Line Items] Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year Weighted-average risk rating Financing Receivable, Weighted Average Risk Rating Financing Receivable, Weighted Average Risk Rating Total Liabilities Total liabilities Liabilities Currency [Axis] Currency [Axis] Percentage to aggregate loans receivable portfolio Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage Number of non-employee directors eligible for annual compensation Board Of Directors, Number Of Directors Eligible For Compensation Board Of Directors, Number Of Directors Eligible For Compensation Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Depreciation and amortization expense Real Estate Owned, Depreciation And Amortization Expense Real Estate Owned, Depreciation And Amortization Expense Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] 2025 FL5 Underlying Collateral Assets 2025 FL5 Underlying Collateral Assets [Member] 2025 FL5 Underlying Collateral Assets Shares of class A common stock issued, net Stock Issued During Period, Value, New Issues Investment risk management committee Investment Risk Management Committee [Member] Investment Risk Management Committee Variable Rate [Axis] Variable Rate [Axis] Counterparty Name [Axis] Counterparty Name [Axis] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Accrued management and incentive fees payable Accrued Management And Incentive Fees Payable Accrued management and incentive fees payable. Collateral deposited under derivative agreements Collateral Already Posted, Aggregate Fair Value