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BSPRT 2023-FL10 Issuer, Ltd. [Member] BSPRT 2023-FL10 Issuer, Ltd. Total Revenue/Investment Income Referral fee income Revenue from Contract with Customer, Excluding Assessed Tax Transfer to held for sale Mortgage Loans On Real Estate, Transfer To Held For Sale Mortgage Loans On Real Estate, Transfer To Held For Sale Borrowings on repurchase agreements and revolving credit facilities - commercial mortgage loans Proceeds From Securities Purchased Under Agreements To Resell, Loans Receivable Proceeds from Securities Purchased under Agreements to Resell, Loans Receivable Schedule of Derivative Liabilities at Fair Value Schedule of Derivative Liabilities at Fair Value [Table Text Block] Schedule of Equity Method Investments Equity Method Investments [Table Text Block] Zelda PG JV HoldCo LLC Zelda PG JV HoldCo LLC [Member] Zelda PG JV HoldCo LLC Common stock repurchases Common stock shares repurchased Stock Repurchased During Period, Value Percent of excess total return Related Party Transaction Subordinated Participation In Asset Sale Fee Related Party Transaction Subordinated Participation In Asset Sale Fee Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Carrying Value Intangible Asset, Excluding Goodwill, before Accumulated Amortization Schedule of Real Estate Owned, Held For Sale Real Estate Owned, Held For Sale [Table Text Block] Real Estate Owned, Held For Sale Interest payable Increase (Decrease) in Interest Payable, Net Sales/paydowns Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Business Combination, Pro Forma Information [Table] Business Combination, Pro Forma Information [Table] Property transferred from real estate owned, held for sale to real estate owned, held for investment Property Transferred From Real Estate Owned, Held-for-Investment To Real Estate Owned, Held-for-Investment Property Transferred From Real Estate Owned, Held-for-Investment To Real Estate Owned, Held-for-Investment Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Four Finite-Lived Intangible Assets, Amortization Expense, after Year Four Diluted Numerator Diluted Numerator [Abstract] Diluted Numerator GS Repo Facility GS Repo Facility [Member] GS Repo Facility June 2025 Multifamily June 2025 Multifamily [Member] June 2025 Multifamily Equity Method Investment [Table] Equity Method Investment [Table] Escrow deposit Escrow Deposit Weighted average risk rating of loans Weighted Average Risk Rating Of Loans Weighted Average Risk Rating of Loans Southwest Southwest [Member] Southwest Multifamily Multifamily [Member] Gain/(loss) on derivatives Derivative, Gain (Loss) on Derivative, Net Non-Performing Financial Instruments [Roll Forward] Non-Performing Financial Instruments [Roll Forward] Non-Performing Financial Instruments Allowance acquired in acquisition Loss Contingency Accrual Allowance Acquired in Acquisition Loss Contingency Accrual Allowance Acquired in Acquisition Accrued interest Accrued Interest Receivable, Net, Current Accrued Interest Receivable, Net, Current Repurchase agreements, Net Amount of Liabilities Presented on the Balance Sheet Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, after Offset Related Party Transaction [Domain] Related Party Transaction [Domain] Business Combinations Business Combination [Text Block] Other financings Notes Payable, Fair Value Disclosure Options Equity Option [Member] 2031 and beyond Lessor, Operating Lease, Payment to be Received, After Year Four Lessor, Operating Lease, Payment to be Received, After Year Four Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] ARIZONA ARIZONA Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Schedule of Changes in Allowance for Credit Losses Financing Receivable, Allowance for Credit Loss [Table Text Block] Common stock, shares issued (in shares) Common Stock, Shares, Issued VIE assets, measured at fair value VIE Assets, Measured At Fair Value [Member] VIE Assets, Measured At Fair Value Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fixed Rate Fixed Rate [Member] Fixed Rate Product and Service [Domain] Product and Service [Domain] Depreciation expense Real Estate Owned, Depreciation Real Estate Owned, Depreciation Class of Stock [Line Items] Class of Stock [Line Items] California CALIFORNIA Units of partnership interest, amount (in shares) Units of Partnership Interest, Amount Gain/(loss) on other real estate investments Gains (Losses) on Sales of Other Real Estate Net income (loss) attributable to Franklin BSP Realty Trust, Inc. Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Termination Date Trading Arrangement Termination Date Exit capitalization rate Exit Capitalization Rate Exit Capitalization Rate Subsequent Events [Abstract] Subsequent Events [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Net Amount Derivative Asset, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Due to affiliates Other Liabilities, Current Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Contributions/(distributions) in non-controlling interest, net Noncontrolling Interest, Net Increase (Decrease) Noncontrolling Interest, Net Increase (Decrease) Fair Value as of Grant Date Award Grant Date Fair Value Goodwill [Table] Goodwill [Table] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Remaining amount available under share repurchase program Share Repurchase Program, Remaining Authorized, Amount Arrangement Duration Trading Arrangement Duration Repurchase agreements, gross amounts not offset on the balance sheet, Cash Collateral Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Retail Retail Site [Member] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items] Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Finite-lived intangible, carrying value Intangible Asset, Finite-Lived, before Accumulated Amortization Total income Revenues Income/(loss) from equity method investments Income/(loss) from equity method investments Income (Loss) from Equity Method Investments Accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Restricted Shares and Restricted Stock Units Restricted Stock and Restricted Stock Units [Member] Restricted Stock and Restricted Stock Units Number of extension options Debt Instrument, Number Of Extension Options Debt Instrument, Number of Extension Options Goodwill [Roll Forward] Goodwill [Roll Forward] Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Award Type [Domain] Award Type [Domain] Foreclosed Property Construction In Progress Foreclosed Property Construction In Progress [Member] Foreclosed Property Construction In Progress 2026 (October-December) Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Level III Fair Value, Inputs, Level 3 [Member] Asset Pledged as Collateral Asset Pledged as Collateral [Member] Shares Treasury Stock, Shares, Acquired 2027 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One Ownership percentage Noncontrolling interest, ownership percentage by noncontrolling owners Subsidiary, Ownership Percentage, Noncontrolling Owner Geographical [Axis] Geographical [Axis] CLO cash held by servicer Restricted cash Restricted Cash Total future minimum rent Lessor, Operating Lease, Payment to be Received Proceeds from sale of commercial mortgage loans, held for investment Proceeds From Sale Of Commercial Mortgage Loans Held-For-Investment Proceeds From Sale Of Commercial Mortgage Loans Held-For-Investment Commercial Mortgage Loans Held For Sale Commercial Mortgage Loans Held For Sale [Member] Commercial Mortgage Loans Held For Sale Legal Entity [Axis] Legal Entity [Axis] Proceeds from sale/(purchase) of derivative instruments Payments for (Proceeds from) Derivative Instrument, Investing Activities Acquired MSRs at July 1, 2025 Payments to Acquire Mortgage Servicing Rights (MSR) Transfer to real estate owned Mortgage Loans On Real Estate, Transfer On Foreclosure Mortgage Loans on Real Estate, Transfer on Foreclosure Repurchases paid Treasury Stock, Value, Acquired, Cost Method Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Cash, cash equivalents and restricted cash, Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Derivative instruments, at fair value, Cash Collateral Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Intangible Asset, Finite-Lived [Table] Intangible Asset, Finite-Lived [Table] Non-NEOs Non-NEOs [Member] Provision for Credit Losses Financing Receivable, Allowance for Credit Loss [Roll Forward] Equity method investment, ownership percentage Equity Method Investment, Ownership Percentage NewPoint JV LLC NewPoint JV LLC [Member] NewPoint JV LLC Purchase of NewPoint Holdings JV LLC Purchase of NewPoint Holdings JV LLC Payments to Acquire Businesses, Gross 2028 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Accrued compensation Business Combination, Recognized Liability Assumed, Accrued Compensation Business Combination, Recognized Liability Assumed, Accrued Compensation Schedule of Debt Schedule of Debt [Table Text Block] Investment, Name [Domain] Investment, Name [Domain] GEORGIA GEORGIA Leases Lessee, Operating Leases [Text Block] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Payments for common stock repurchases Payments for Repurchase of Common Stock Statistical Measurement [Axis] Statistical Measurement [Axis] Schedule of Derivative Instruments, Gain (Loss) Derivative Instruments, Gain (Loss) [Table Text Block] Award Type [Axis] Award Type [Axis] 2026 (October-December) Lessor, Operating Lease, Payment to be Received, Remainder of Fiscal Year Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accumulated deficit Retained Earnings (Accumulated Deficit) Deferred fees and other items SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Other Addition Florida FLORIDA Product and Service [Axis] Product and Service [Axis] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Borrowings on collateralized loan obligations Proceeds from Issuance of Secured Debt Common Stock Common Stock [Member] Interest on escrows Interest Earned on Escrows Interest Earned on Escrows Operating lease cost Operating Lease, Cost JPM Repo Facility JPM Repo Facility [Member] JPM Repo Facility [Member] Equity Method Investment, Nonconsolidated Investee or Group of Investees Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Derivative Contract [Domain] Derivative Contract [Domain] 2027 Unrecorded Unconditional Purchase Obligation, to be Paid, Year One Equity Method Investment, Aggregate Cost Equity Method Investment, Aggregate Cost Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Denver, CO COLORADO Loss sharing obligations Guarantee Obligations Included In Allowance For Loss Sharing Obligations Guarantee Obligations Included In Allowance For Loss Sharing Obligations Present value, discount rate, percentage Present Value, Discount Rate, Percentage Present Value, Discount Rate, Percentage Real Estate Property Ownership [Axis] Real Estate Property Ownership [Axis] Realized gain/(loss) on real estate securities, available for sale Debt Securities, Available-for-Sale, Realized Gain (Loss) Total liabilities, redeemable convertible preferred stock and equity Liabilities and Equity Variable lease cost Variable Lease, Cost Employee Stock Option Share-Based Payment Arrangement, Option [Member] Originations Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Non-controlling interest Equity, Attributable to Noncontrolling Interest Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Related Party [Domain] Related and Nonrelated Parties [Domain] Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital 2029 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three 2026 (October-December) 2026 (October - December) Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Property, Plant and Equipment, Type [Domain] Long-Lived Asset, Class [Domain] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Loans transferred from commercial mortgage loans, held for investment to real estate owned, held for investment Real Estate Owned, Transfer to Real Estate Owned Less: Preferred stock dividends Less: Preferred stock dividends Preferred Stock Dividends and Other Adjustments Fees per the fee arrangement Fees Per The Fee Arrangement Fees Per The Fee Arrangement Preferred stock, $0.01 par value; 100,000,000 shares authorized, 7.5% Cumulative Redeemable Preferred Stock, Series E, 10,329,039 shares issued and outstanding as of September 30, 2026 and December 31, 2025 Perpetual preferred stock Preferred Stock, Value, Issued UPB Loan, Held-in-Portfolio, Principal Outstanding General allowance for credit losses General (provision)/benefit for credit losses General Allowance for Credit Losses Allowance for Credit Loss, General [Member] Allowance for Credit Loss, General Adjustment to Compensation: Adjustment to Compensation [Axis] Loan commitments and forward sale commitments, net Loan Commitments And Forward Sale Commitments, Fair Value Loan Commitments And Forward Sale Commitments, Fair Value Reclassification adjustment for amounts included in net income/(loss) Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Credit Concentration Risk Credit Concentration Risk [Member] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Cash payments for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Common stock purchased through distribution reinvestment plan (in shares) Stock Purchased During Period, Shares, Dividend Reinvestment Plan Stock Purchased During Period, Shares, Dividend Reinvestment Plan Less: Participating securities' share in earnings Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Other expenses Other General Expense Credit Facility [Axis] Credit Facility [Axis] Total assets, at fair value Total assets, at fair value Assets, Fair Value Disclosure Schedule of Repurchase Agreements Schedule of Repurchase Agreements [Table Text Block] Acquisition fees and expenses, including amount capitalized Acquisition Fees And Expenses Including Amount Capitalized [Member] Acquisition Fees And Expenses Including Amount Capitalized [Member] Name Measure Name Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Total redeemable convertible preferred stock Redeemable convertible preferred stock Convertible Preferred Stock, Nonredeemable or Redeemable, Issuer Option, Value Additional Paid-In Capital Additional Paid-in Capital [Member] Intangible Asset, Indefinite-Lived, Class [Axis] Intangible Asset, Indefinite-Lived, Class [Axis] Commercial mortgage loans, held for sale, measured at fair value Business Combination, Recognized Asset Acquired, Mortgages Held For Sale Fair Value Disclosure Business Combination, Recognized Asset Acquired, Mortgages Held For Sale Fair Value Disclosure Accrued interest receivable Accrued interest receivable Interest Receivable Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash and Cash Equivalent Company Selected Measure Amount Company Selected Measure Amount Depreciation and amortization Depreciation, Depletion and Amortization Discount rate Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Repurchase agreements, Gross Amounts of Recognized Liabilities Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, before Offset Real Estate Debt and Other Real Estate Investments Real Estate Debt [Member] Real Estate Debt [Member] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Accounts and Financing Receivables [Table] Real Estate [Abstract] Real Estate [Abstract] Weighted-average remaining lease term (in year) Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Collateralized loan obligation excluded Secured Debt Excluded Secured Debt Excluded Barclays Repo Facility Barclays Repo Facility [Member] Barclays Repo Facility [Member] Customer Concentration Risk Customer Concentration Risk [Member] Award Timing Method Award Timing Method [Text Block] Unfunded Commitments Under Commercial Mortgage Loans Loan Origination Commitments [Member] Net change in cash, cash equivalents and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forecast Forecast [Member] Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Junior Note III Junior Subordinated Note III, Maturing September 2036 [Member] Junior Subordinated Note III, Maturing September 2036 Accumulated Depreciation Real Estate Owned, Accumulated Depreciation Mortgage Servicing Rights Servicing Revenue Transfers and Servicing of Financial Assets [Text Block] Par Value Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Losses Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Losses 2028 Lessor, Operating Lease, Payment to be Received, Year Two Net income/(loss) attributable to Franklin BSP Realty Trust, Inc. Net income/(loss) attributable to Franklin BSP Realty Trust, Inc. Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Operating Partner Operating Partner [Member] Operating Partner Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Profit Distribution Hurdle Rate [Axis] Profit Distribution Hurdle Rate [Axis] Profit Distribution Hurdle Rate Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Restatement Determination Date: Restatement Determination Date [Axis] Schedule of Changes in Accumulated Other Comprehensive Income/(Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Amortized cost, beginning of period Amortized cost, end of period Mortgage Loans on Real Estate, Commercial and Consumer, Net Seller-based financing on sales of real estate owned, held for sale Seller Based Financing On Sales Of Real Estate Owned Held For Sale Seller Based Financing On Sales Of Real Estate Owned Held For Sale Amortization/accretion of fees and other items Mortgage Loans On Real Estate, Accretion (Amortization) Of Discounts And Premiums Mortgage Loans on Real Estate, Accretion (Amortization) of Discounts and Premiums WF Repo Facility WF Repo Facility [Member] WF Repo Facility [Member] Income Revenues [Abstract] Treasury notes US Treasury Notes Securities [Member] CECL reserves impact Impact Of Adopting Current Expected Credit Losses Impact Of Adopting Current Expected Credit Losses Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] May 2022 Multifamily May 2022 Multifamily [Member] May 2022 Multifamily Weighted Avg. Life (in Years) Intangible Asset, Finite-Lived, Remaining Amortization Period Intangible Asset and Goodwill Intangible Asset and Goodwill [Table Text Block] New Jersey NEW JERSEY Statistical Measurement [Domain] Statistical Measurement [Domain] JPM WH Line of Credit JPM WH Line of Credit [Member] JPM WH Line of Credit Document Fiscal Year Focus Document Fiscal Year Focus NORTH CAROLINA NORTH CAROLINA Derivative instruments, at fair value, Gross Amounts Offset on the Balance Sheet Derivative Liability, Subject to Master Netting Arrangement, Asset Offset Acquisition expenses Business Combination, Acquisition-Related Cost, Expense Agency License Intangibles Agency License Intangibles [Member] Agency License Intangibles Common stock, $0.01 par value, 900,000,000 shares authorized, 75,881,209 and 81,553,982 shares issued and outstanding as of September 30, 2026 and December 31, 2025, respectively Common stock value Common Stock, Value, Issued Weighted average servicing fee (as basis points) Contractually Specified Servicing Fees, Percentage Contractually Specified Servicing Fees, Percentage Interest Expense Interest Expense, Operating and Nonoperating 2027 Lessee, Operating Lease, Liability, to be Paid, Year One Shares cancelled for tax withholding on vested equity rewards Payment, Tax Withholding, Share-Based Payment Arrangement Schedule of Collateralized Loan Obligations by Tranche Schedule of Long-Term Debt Instruments [Table Text Block] Share repurchase program, increase (decrease) in authorized, amount Share Repurchase Program, Increase (Decrease) In Authorized, Amount Share Repurchase Program, Increase (Decrease) In Authorized, Amount Line of Credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Industrial Industrial Property [Member] Less than 90 days past due Financial Asset, Less Than 90 Days Past Due [Member] Financial Asset, Less Than 90 Days Past Due Indefinite lived intangibles: Intangible Asset, Excluding Goodwill, Indefinite-Lived [Abstract] Amendment Flag Amendment Flag Goodwill [Line Items] Goodwill [Line Items] Credit default swaps Credit Default Swap [Member] Acquisitions and originations SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, New Mortgage Loan Loan repurchase option liability Business Combination, Recognized Liability Assumed, Loan Repurchase Option Liability Business Combination, Recognized Liability Assumed, Loan Repurchase Option Liability New York NEW YORK Interest paid Interest Paid, Including Capitalized Interest, Operating and Investing Activities Unrealized (Loss) Unrealized loss Unrealized (Loss) Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Schedule of Available-for-Sale Securities Debt Securities, Available-for-Sale [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Origination of commercial mortgage loans, held for sale, measured at fair value Payment for Origination, Loan, Mortgage, Held-for-Sale Private Label Private Label [Member] Private Label Durham, NC Durham, North Carolina 1 [Member] Durham, North Carolina 1 Initial risk rating Initial Risk Rating Of Loans Initial Risk Rating of Loans Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Transfers into Level III Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Charge offs from specific allowance for credit losses Mortgage Loans On Real Estate, Charge-Off Mortgage Loans On Real Estate, Charge-Off Entity Address, State or Province Entity Address, State or Province Licensing Agreements Licensing Agreements [Member] Non-performing loan amortized cost at beginning of year, January 1 Non-performing loan amortized cost end of period Financing Receivable, Excluding Accrued Interest, Nonaccrual PEO Total Compensation Amount PEO Total Compensation Amount Notional Derivative, Notional Amount Share Repurchase Program [Domain] Share Repurchase Program [Domain] Basic weighted average shares outstanding (in shares) Weighted-average common shares outstanding for basic earnings per share (in shares) Weighted Average Number of Shares Outstanding, Basic Rocky Mountain Rocky Mountain [Member] Rocky Mountain Schedule of Costs Incurred From Arrangements with Advisor and Affiliates Schedule of Related Party Transactions [Table Text Block] Collateralized loan obligations Secured Debt Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Loss Contingencies [Line Items] Loss Contingencies [Line Items] 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Unfunded Unfunded Loan Commitment [Member] Maryland MARYLAND Far West Far West [Member] Far West Noncontrolling interest in joint ventures Noncontrolling Interest in Joint Ventures Forward sale commitments Forward Sale Commitments [Member] Forward Sale Commitments Accrued interest receivable Increase (Decrease) in Accrued Interest Receivable, Net Commercial Mortgage Loans, Held for Investment Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Document Information [Line Items] Document Information [Line Items] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Class of Stock [Axis] Class of Stock [Axis] DRIP Dividend Reinvestment And Direct Stock Purchase Plan (DRIP) [Member] Dividend Reinvestment And Direct Stock Purchase Plan (DRIP) Realized (gain)/loss on sale of available for sale securities, measured at fair value Debt Securities, Available-for-Sale, Trading, Gain (Loss) Debt Securities, Available-for-Sale, Trading, Gain (Loss) Basic net income/(loss) applicable to common stockholders Basic net income/(loss) applicable to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Accumulated Amortization Intangible Asset, Finite-Lived, Accumulated Amortization Weighted Average Days to Maturity Debt Instrument, Weighted Average Days To Maturity Debt Instrument, Weighted Average Days To Maturity Repo and revolving credit facilities, commercial mortgage loans, capacity Line of Credit Facility, Maximum Borrowing Capacity Net borrowings/(paydowns) on repurchase agreements - real estate securities, less than 90 days maturity Proceeds From (Repayment Of) Real Estate Security Repurchase Agreements Proceeds from Real Estate Security Repurchase Agreements Straight line rental income Straight Line Rent Commercial mortgage loans, held for investment, net of allowance for credit losses of $71,932 and $38,302 as of September 30, 2026 and December 31, 2025, respectively Total commercial mortgage loans, held for investment, net Total commercial mortgage loans, held for investment, net Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss Net unrealized loss on CLO bonds Debt Securities, Available-for-Sale, Accumulated Net Unrealized Gain (Loss), before Tax Debt Securities, Available-for-Sale, Accumulated Net Unrealized Gain (Loss), before Tax Allowance for loss sharing Business Combination, Recognized Liability Assumed, Allowance for Loss Sharing Business Combination, Recognized Liability Assumed, Allowance for Loss Sharing Recently Issued Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Land Land [Member] Non-Controlling Interest Noncontrolling Interest [Member] Bridge Bridge [Member] Bridge Amortization of deferred financing costs Amortization of Debt Issuance Costs Net income/(loss) applicable to common stock, basic Net Income (Loss) Available to Common Stockholders, Basic, Including Undistributed Earnings (Loss) Allocated to Participating Securities Net Income (Loss) Available to Common Stockholders, Basic, Including Undistributed Earnings (Loss) Allocated to Participating Securities Intangible asset Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill Common stock issued under dividend reinvestment plan (in shares) Stock Issued During Period, Shares, Dividend Reinvestment Plan Unsecured debt, amount outstanding Outstanding principal Long-Term Debt Transaction rate (percent) Related Party Transaction, Rate 2024-FL11 Issuer Collateralized Loan Obligations Issued in 2023-FL10 [Member] Collateralized Loan Obligations Issued in 2023-FL10 Year three, originated in prior fiscal year two Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year Mortgage impairment insurance MSR impairment Mortgage Servicing Rights (MSR) Impairment (Recovery) Mortgage note payable Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure Net cash (used in)/provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Cash Collateral Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash Not Offset Preferred stock converted to common stock, per share stock consideration (in shares) Conversion of Stock, Preferred Stock Converted To Common Stock, Per Share Stock Consideration Conversion of Stock, Preferred Stock Converted To Common Stock, Per Share Stock Consideration Redeemable Convertible Preferred Stock and Equity Transactions Equity [Text Block] Security Exchange Name Security Exchange Name Total stockholders' equity Net Assets, Equity, Attributable to Parent Net Assets, Equity, Attributable to Parent Portland, OR Portland, Oregon [Member] Portland, Oregon Credit Loss Status [Domain] Credit Loss Status [Domain] Affordable Affordable [Member] Affordable Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Modification accounted for as repayment and new loan Modification Accounted For As Repayment And New Loan Modification Accounted For As Repayment And New Loan Real estate owned, held for sale Assets, Net Real Estate, Held-for-Sale Common stock reserved for issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized Other Other Real Estate Property [Member] Other Real Estate Property Business Combination, Pro Forma Information [Line Items] Business Combination, Pro Forma Information [Line Items] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Intangible assets, net of amortization Finance Lease, Right-of-Use Asset, after Accumulated Amortization Name Outstanding Recovery, Individual Name Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Commercial mortgage loans, held for investment Debt Security, Mortgage-Backed, Held-to-Maturity, Fair Value Disclosure Share-based compensation (in shares) Shares Granted, Shares, Share-Based Payment Arrangement, after Forfeiture, Net Shares Granted, Shares, Share-Based Payment Arrangement, after Forfeiture, Net Geographical [Domain] Geographical [Domain] Indefinite-lived intangible, carrying value Intangible Asset, Excluding Goodwill, Indefinite-Lived Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Benefit Street Partners LLC Benefit Street Partners LLC [Member] Benefit Street Partners LLC [Member] Riverwalk Aker BSP Venture LLC Riverwalk Aker BSP Venture LLC [Member] Riverwalk Aker BSP Venture LLC 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Business Combination, Voting Equity Interest Acquired, Percentage Diluted weighted average shares outstanding (in shares) Weighted-average common shares outstanding for diluted earnings per share (in shares) Weighted Average Number of Shares Outstanding, Diluted Southeast Southeast [Member] Southeast Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Entity Emerging Growth Company Entity Emerging Growth Company Related Party Transaction [Line Items] Related Party Transaction [Line Items] Total gross carrying value of loans Amortized cost Total Amortized Cost Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss Underlying Security Market Price Change Underlying Security Market Price Change, Percent Derivative Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Jeffersonville JV, Affiliate Jeffersonville JV, Affiliate [Member] Jeffersonville JV, Affiliate 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Rights MSRs Pay Offs Mortgage Servicing Rights MSRs Variable interest entity (“VIE”) assets, measured at fair value Variable Interest Entity Assets Variable Interest Entity Assets Extension period on initial maturity date Debt Instrument, Extension On Initial Maturity Date Debt Instrument, Extension on Initial Maturity Date Administrative services expenses Administrative services expenses General and Administrative Expense Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Number of real estate properties Number of Real Estate Properties Repurchase agreements - commercial mortgage loans Repurchase agreements, commercial mortgage loans Commercial Mortgage-Backed Securities [Member] Change in net assets of consolidated VIE, CMBS trust Variable Interest Entity Income (loss) Variable Interest Entity Income (loss) Share Repurchase Program [Axis] Share Repurchase Program [Axis] Class of Stock [Domain] Class of Stock [Domain] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] 2025-FL12 Issuer Collateralized Loan Obligations Issued in 2024-FL11 Issuer [Member] Collateralized Loan Obligations Issued in 2024-FL11 Issuer June 2021 Multifamily June 2022 Multifamily [Member] June 2022 Multifamily Real estate investments, joint ventures Real Estate Investments, Joint Ventures Schedule of Shares Outstanding Schedule of Stock by Class [Table Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Revenue, Product and Service Benchmark Revenue, Product and Service Benchmark [Member] Barclays Capital Inc. Barclays Capital Inc [Member] Barclays Capital Inc [Member] Purchase of real estate owned and capital expenditures Payments To Acquire Real Estate Owned Payments To Acquire Real Estate Owned Real estate owned, net of depreciation Real Estate Acquired Through Foreclosure Petroleum Reserves [Axis] Petroleum Reserves [Axis] Servicing portfolio Financing Receivable, Loan Servicing Portfolio Financing Receivable, Loan Servicing Portfolio Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Total Purchase Price Purchase price Business Combination, Consideration Transferred Entity Filer Category Entity Filer Category Supplemental disclosures of cash flow information: Supplemental Cash Flow Elements [Abstract] Mixed Use Mixed Use [Member] Mixed Use [Member] Payment of software development costs Payments to Develop Software Schedule of Offsetting Liabilities Offsetting Liabilities [Table Text Block] Realized Gain/(Loss) Gain (Loss) on Derivative Instruments, Net, Pretax Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Financial Asset, Period Past Due [Axis] Financial Asset, Aging [Axis] Distributions from equity method investments Proceeds from Equity Method Investment, Distribution Equity Method Investments and Joint Ventures [Abstract] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Loan commitments Loan Purchase Commitments [Member] Repurchase agreements, Gross Amounts Offset on the Balance Sheet Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, Asset Offset Entity Address, Address Line Two Entity Address, Address Line Two Schedule of Stock by Class [Table] Stock, Class of Stock [Table] Net income/(loss) Net income/(loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Barclays Revolver Facility Barclays Revolver Facility [Member] Barclays Facility [Member] Hospitality Property Hospitality Property [Member] Hospitality Property Revenue Business Combination, Pro Forma Information, Pro Forma Revenue Derivative instruments, measured at fair value Treasury notes Derivative Liability Entity Address, Address Line One Entity Address, Address Line One (Provision)/benefit for income tax Income Tax Expense (Benefit) Series H Preferred Stock Series H Preferred Stock [Member] Charge offs for specific allowance for loss sharing Loss Contingency Accrual, Payments Principles of Consolidation Consolidation, Policy [Policy Text Block] Offsetting Derivative Liabilities Offsetting Derivative Liabilities [Abstract] Other financings Note-on-Note Financing [Member] Note-on-Note Financing Variable Interest Entity, Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Discounted Cash Flow Valuation Technique, Discounted Cash Flow [Member] Nonaccrual Nonaccrual [Member] Nonaccrual Principal repayments received on commercial mortgage loans, held for investment Proceeds from Collection of Loans Receivable Statement [Table] Statement [Table] 2030 and beyond Unrecorded Unconditional Purchase Obligation, to be Paid, after Year Four and After Year Four Unrecorded Unconditional Purchase Obligation, to be Paid, Year Four and After Year Four Subsequent Return Hurdle Rate Subsequent Return Hurdle Rate [Member] Subsequent Return Hurdle Rate Year two, originated in prior fiscal year one Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year Schedule of Loans on Nonaccrual Status Financing Receivable, Nonaccrual [Table Text Block] Loans transferred from commercial mortgage loans, held for investment to commercial mortgage loans, held for sale Loans Transferred To Commercial Mortgage Loans, Held-for-Investment Loans Transferred To Commercial Mortgage Loans, Held-for-Investment Assets Gross Amounts of Recognized Assets Derivative Asset, Subject to Master Netting Arrangement, before Offset Schedule of Real Estate Owned, Held For Investment Real Estate Owned, Held For Investment [Table Text Block] Real Estate Owned, Held For Investment 2026 Unrecorded Unconditional Purchase Obligation, to be Paid, Remainder of Fiscal Year Liabilities, Net Real Estate Liabilities Associated with Assets Held for Development and Sale Initial maturity period Long-Term Debt, Term Prepaid expenses and other assets Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract]