Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Hospitality Hotel [Member] Trading Arrangement: Trading Arrangement [Axis] Total BTIG, LLC, Gryphon Mutual Property Americas IC, Internal audit services, Lexington National Land Services, Blackstone Securities Partners L.P [Member] BTIG, LLC, Gryphon Mutual Property Americas IC, Internal audit services, Lexington National Land Services, Blackstone Securities Partners L.P Wtd. Avg. Yield/Cost, collateral assets Securitized Debt Obligations Yield Rate Securitized Debt Obligations Yield Rate Maximum Maximum [Member] Title of 12(b) Security Title of 12(b) Security Deferred Stock Units Deferred Stock Units [Member] Deferred Stock Units Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Principal collections, sales proceeds, and cost-recovery proceeds from loans receivable Proceeds from Sale and Collection of Loans Receivable Adjustment to Compensation, Amount Adjustment to Compensation Amount Real Estate [Line Items] Real Estate [Line Items] Segment Reporting [Abstract] Schedule of Intangible Asset, Finite-Lived, and Capitalized Cost, Software to be Sold, Leased, or Marketed, Estimated Amortization Expense Intangible Asset, Finite-Lived, and Capitalized Cost, Software to be Sold, Leased, or Marketed, Estimated Amortization Expense [Table Text Block] Maximum guarantee Guarantor Obligations, Maximum Exposure, Undiscounted Count, collateral assets Count, collateral assets Debt Instrument, Collateral Amount, Number Of Loans Debt Instrument, Collateral Amount, Number Of Loans Amortization of deferred fees on loans Amortization of fees and other items Amortization of Deferred Loan Origination Fees, Net Derivative Instrument [Axis] Derivative Instrument [Axis] Total loans receivable Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract] Issuance of restricted class A common stock, net (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Retained interest with financing capital markets base amount Loan, Managed and Securitized or Asset-Backed Financing Arrangement, Principal Outstanding Other Europe Other Europe [Member] Other Europe. Measurement Frequency [Axis] Measurement Frequency [Axis] Principal fundings of loans receivable Payments for (Proceeds from) Loans Receivable Conversion price (in dollars per share) Debt Instrument, Convertible, Conversion Price Open Market, Dividend Reinvestment Open Market, Dividend Reinvestment [Member] Open Market, Dividend Reinvestment Impaired loans Impaired Loans [Member] Impaired Loans [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Covenants, minimum tangible net worth Debt Instrument, Covenant, Tangible Net Worth, Minimum Debt Instrument, Covenant, Tangible Net Worth, Minimum Buy USD / Sell GBP Forward Buy USD / Sell GBP Forward Foreign Exchange Contract Buy United States Dollar Sell Great Britain Pound [Member] Foreign Exchange Contract Buy United States Dollar Sell Great Britain Pound. Principal balance Loans receivable Loan receivable, net, face amount Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process Two Property Through Foreclosure Two Property Through Foreclosure [Member] Two Property Through Foreclosure Transactions With Related Parties Related Party Transactions Disclosure [Text Block] Consolidated Entities [Domain] Consolidated Entities [Domain] 2021 FL4 Senior Collateralized Loan Obligation 2021 FL4 Senior Collateralized Loan Obligation [Member] 2021 FL4 Senior Collateralized Loan Obligation Distributions to non-controlling interests Payments to Noncontrolling Interests Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff Proceeds from disposition of owned real estate Proceeds from Sale of Other Real Estate Common shares reserved for issuance (in shares) Dividend Reinvestment And Direct Stock Purchase Plan, Shares Authorized Dividend Reinvestment And Direct Stock Purchase Plan, Shares Authorized Annual cash compensation Annual Director Compensation Annual Director Compensation Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Asset Acquisition [Axis] Asset Acquisition [Axis] Number of shares of restricted class A common stock outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number All-in cost Debt Instrument Interest Rate Stated Percentage Including Amortization Cost Debt Instrument Interest Rate Stated Percentage Including Amortization Cost Vest in 2026 Share-Based Payment Arrangement, Tranche One [Member] Income from loans and other investments, net Interest And Fee Income, Loans And Leases, Net Of Interest Expense, Operating Interest And Fee Income, Loans And Leases, Net Of Interest Expense, Operating Gross charge-offs Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] Collateral Book Value, collateral assets Debt Instrument, Collateral Amount Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Number of assets in special servicing under CLOs Collateralized Loan Obligations, Number Of Assets Collateralized Loan Obligations, Number Of Assets Percentage of stock Common Stock, Shares, Outstanding, Percentage Common Stock, Shares, Outstanding, Percentage Number of reporting segments Number of Reportable Segments Schedule of Outstanding Interest Rate Derivatives Designated as Cash Flow Hedges of Interest Rate Risk Schedule of Derivative Instruments [Table Text Block] Entity Address, City or Town Entity Address, City or Town Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Walker & Dunlop Walker & Dunlop [Member] Walker & Dunlop. Receivables [Abstract] Receivables [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Relationship to Entity [Domain] Title and Position [Domain] Year one Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff Total Intangible Asset, Finite-Lived, after Accumulated Amortization Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Return of capital from unconsolidated entities Proceeds from Equity Method Investment, Distribution, Return of Capital Senior Loans Senior Loans [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Other comprehensive income (loss) Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] 2029 Lessor, Operating Lease, Payment to be Received, Year Three 1 1 Risk Rating, One [Member] Risk Rating One [Member] Subtotal UNITED STATES Debt instrument, variable interest rate, type [Extensible Enumeration] Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Subtotal General And Administrative Expense, Excluding Non-Cash Compensation Expense General And Administrative Expense, Excluding Non-Cash Compensation Expense 2029 Below Market Lease, Amortization Income, Year Three Loan repayments, sales, and cost-recovery proceeds Financing Receivable, Before Allowance For Credit Loss, Fee And Loan In Process, Sale And Collection Of Finance Receivables And Cost-Recovery Proceeds Financing Receivable, Before Allowance For Credit Loss, Fee And Loan In Process, Sale And Collection Of Finance Receivables And Cost-Recovery Proceeds Other comprehensive income (loss) Other Comprehensive Income (Loss), before Tax [Abstract] Use of Estimates Use of Estimates, Policy [Policy Text Block] Related Party [Axis] Related and Nonrelated Parties [Axis] Agency Multifamily Lending Partnership Revenue from Contract with Customer [Policy Text Block] Cost-recovery proceeds Financing Receivable, Excluding Accrued Interest, Unamortized Loan Fee (Cost) And Purchase Premium (Discount), Sale And Collection Of Finance Receivables And Cost-Recovery Proceeds, Net Financing Receivable, Excluding Accrued Interest, Unamortized Loan Fee (Cost) And Purchase Premium (Discount), Sale And Collection Of Finance Receivables And Cost-Recovery Proceeds, Net Wtd. avg. all-in cost (percentage) Line Of Credit Facility, Weighted Average All-In Cost Line Of Credit Facility, Weighted Average All-In Cost Current expected credit loss reserve CECL reserve CECL reserve Beginning balance Ending balance Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest Document Period End Date Document Period End Date Net Lease Joint Venture Net Lease Joint Venture [Member] Net Lease Joint Venture Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Principal balance Face Value Debt Instrument, Face Amount All-in cost Debt Instrument, Interest Rate, Effective Percentage Number of REO assets classified as held for sale investment Real Estate Owned, Number Of Assets Classified As Held-For-Sale Real Estate Owned, Number Of Assets Classified As Held-For-Sale Investments in Unconsolidated Entities [Roll Forward] Investments in Unconsolidated Entities [Roll Forward] Investments in Unconsolidated Entities Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares Outstanding, Including Deferred Stock Units Common Stock, Shares Outstanding, Including Deferred Stock Units Collateral deposited under derivative agreements Payments For Collateral Deposit On Derivative Instrument, Investing Activities Payments For Collateral Deposit On Derivative Instrument, Investing Activities Sweden SWEDEN Estimated useful lives (in years) Real Estate Owned, Useful Life Real Estate Owned, Useful Life Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Hedged Liability, Statement of Financial Position [Extensible Enumeration] Hedged Liability, Statement of Financial Position [Extensible Enumeration] Percentage to aggregate loans receivable portfolio Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage Number Of Loans [Domain] Number Of Loans [Domain] Number Of Loans [Domain] Proceeds from issuance of securitized debt obligations Proceeds From Issuance of Collateralized Loan Obligations Proceeds From Issuance of Collateralized Loan Obligations Net (loss) income per share of common stock Earnings Per Share [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Total Liabilities Total liabilities Liabilities Trading Symbol Trading Symbol Discount rate Measurement Input, Discount Rate [Member] Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] Non-U.S. Loans Non US Loans [Member] Non US Loans Schedule of Outstanding Interest Rate Derivatives Designated as Cash Flow Hedges of Interest Rate Risk Schedule of Interest Rate Derivatives [Table Text Block] Accrued capital expenditures on owned real estate Real Estate Owned, Capital Expenditures Incurred But Not Yet Paid Real Estate Owned, Capital Expenditures Incurred But Not Yet Paid Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Company Selected Measure Name Company Selected Measure Name Sale of Stock [Domain] Sale of Stock [Domain] Realized gain on derivative financial instruments, net Realized Gains Losses On Derivative Financial Instruments Net Realized Gains Losses On Derivative Financial Instruments Net Investment in debt securities Investment in debt securities Payments to Acquire Debt Securities, Available-for-Sale Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Fixed Rate Derivative, Fixed Interest Rate Number of directors not eligible for compensation Board Of Directors, Number Of Members Not Eligible For Annual Compensation Board Of Directors, Number Of Members Not Eligible For Annual Compensation Covenants, percentage of tangible assets on cash proceeds from equity issuances Debt Instrument, Covenant, Percentage Of Net Cash Proceeds Of Future Equity Issuances Debt Instrument, Covenant, Percentage Of Net Cash Proceeds Of Future Equity Issuances Year one Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year Credit Facility [Domain] Credit Facility [Domain] Depreciation and amortization of owned real estate Depreciation, Depletion and Amortization, Nonproduction Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Weighted-average index rate floor Financing Receivable, Weighted Average Index Rate Floor Financing Receivable, Weighted Average Index Rate Floor Brio Real Estate Services, LLC, Brio Real Estate (UK) Ltd And Brio Real Estate (AUS) Pty Ltd Brio Real Estate Services, LLC, Brio Real Estate (UK) Ltd And Brio Real Estate (AUS) Pty Ltd [Member] Brio Real Estate Services, LLC, Brio Real Estate (UK) Ltd And Brio Real Estate (AUS) Pty Ltd Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] Dividends declared on common stock and deferred stock units Dividends, total Dividends Secured credit facilities Secured Credit Facility [Member] Secured Credit Facility Net operating losses carried forward Operating Loss Carryforwards Deferred stock unit dividends declared Dividend, Share-Based Payment Arrangement Dividends declared, not paid Accrued dividends payable Dividends Payable Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Buy USD / Sell CHF Forward Foreign Exchange Contract Buy United States Dollar Sell Swiss Franc [Member] Foreign Exchange Contract Buy United States Dollar Sell Swiss Franc B-8 Term Loan B-8 Term Loan Due 2032 [Member] B-8 Term Loan Due 2032 Land Improvements Land Improvements [Member] Operating and other costs Other General and Administrative Expense Award Timing Predetermined Award Timing Predetermined [Flag] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Level 1 Fair Value, Inputs, Level 1 [Member] Conversion rate Debt Instrument, Convertible, Conversion Ratio Fair Value Measurements Fair Value of Financial Instruments, Policy [Policy Text Block] Restricted class A common stock earned Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture Fair value basis adjustment on hedged items Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Long-term debt, fair value Long-Term Debt, Fair Value Blackstone-Advised Investment Vehicles, or the Funds Blackstone-Advised Investment Vehicles, or the Funds [Member] Blackstone-Advised Investment Vehicles, or the Funds. Vesting [Domain] Vesting [Domain] Perform Properties, LLC Perform Properties, LLC [Member] Perform Properties, LLC Concentration Risk Type [Domain] Concentration Risk Type [Domain] Schedule of Below Market Lease, Future Amortization Income Below Market Lease, Future Amortization Income [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Total (loss) gain on derivative instruments Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments Dividends paid on class A common stock Payments of Ordinary Dividends, Common Stock Less: accumulated amortization Intangible Real Estate Liabilities Acquired Through Foreclosure, Accumulated Depreciation Intangible Real Estate Liabilities Acquired Through Foreclosure, Accumulated Depreciation Expiration Date Trading Arrangement Expiration Date Weighted-average all-in yield (percentage) Financing Receivable, Basis Spread on Variable Rate, Weighted Average All-In Yield Financing Receivable, Basis Spread on Variable Rate, Weighted Average All-In Yield Net (decrease) increase in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation 2030 Long-Term Debt, Maturity, Year Four Hedging Relationship [Axis] Hedging Relationship [Axis] Real Estate [Table] Real Estate [Table] Multifamily Property Located San Antonio Multifamily Property Located San Antonio [Member] Multifamily Property Located San Antonio Cash and cash equivalents, fair value Cash and Cash Equivalents, Fair Value Disclosure Total Equity Beginning balance Ending balance Change in equity Equity, Including Portion Attributable to Noncontrolling Interest Building Building [Member] Affiliates of Manager Affiliated Entity [Member] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Other Income and Expenses [Abstract] Other Income and Expenses [Abstract] Interest rate decrease Financing Receivable, Modified, Interest Rate Increase (Decrease) From Modification Financing Receivable, Modified, Interest Rate Increase (Decrease) From Modification Commercial Real Estate Commercial Real Estate [Member] Cash flows from investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] 0.01% to 1.00% floor Financing Receivable, 0.01% To 1.00% Floor [Member] Financing Receivable, 0.01% To 1.00% Floor Unrecognized compensation cost relating to nonvested share-based compensation Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount 2027 Lessor, Operating Lease, Payment to be Received, Year One LendingOne, LLC LendingOne [Member] LendingOne Weighted average price per share (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Per Share Weighted Average Price of Shares Purchased Interest rate swap Interest Rate Swap [Member] CT Investment Management Co., LLC CT Investment Management Co., LLC ("CTIMCO") [Member] CT Investment Management Co., LLC ("CTIMCO") Schedule of Principal Contractual Obligations Contractual Obligation, Fiscal Year Maturity [Table Text Block] Deferred financing costs Debt Issuance Costs, Net PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Secured debt, net Secured Debt [Member] Secured Overnight Financing Rate (SOFR), All-In Cost Secured Overnight Financing Rate (SOFR), All-In Cost [Member] Secured Overnight Financing Rate (SOFR), All-In Cost December 2024 Senior Secured Notes, Due 2029 [Member] Senior Secured Notes, Due 2029 EUR Euro Member Countries, Euro Investment in unconsolidated entities Investment in unconsolidated entities Payments to Acquire Equity Method Investments Interest Rate Debt Instrument, Interest Rate, Stated Percentage 12 Loans 12 Loans [Member] 12 Loans Unrealized loss on foreign currency translation Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Unrealized Gain (Loss) On Foreign Currency Translation Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Unrealized Gain (Loss) On Foreign Currency Translation Total Blackstone Mortgage Trust, Inc. stockholders’ equity Equity, Attributable to Parent Real Estate [Domain] Real Estate [Domain] Return of collateral deposited under derivative agreements Proceeds From Collateral Deposit On Derivative Instrument, Investing Activities Proceeds From Collateral Deposit On Derivative Instrument, Investing Activities Assets Assets Assets Assets [Abstract] 2 2 Risk Rating, Two [Member] Risk Rating Two [Member] Payment Deferral Payment Deferral [Member] Schedule of Net Book Value, Total Loan Exposure and Net Loan Exposure of Loans Receivable Based on Internal Risk Ratings and Credit Quality Indicators Financing Receivable Credit Quality Indicators [Table Text Block] Professional services Professional Fees Fair Value, Nonrecurring Fair Value, Nonrecurring [Member] Insider Trading Policies and Procedures [Line Items] Annual cash compensation paid in cash Annual Director Compensation, Cash Annual Director Compensation, Cash Net Loan Exposure Net loan exposure Financing Receivable, Excluding Accrued Interest, Net Loans Exposure Amount Financing Receivable, Excluding Accrued Interest, Net Loans Exposure Amount Number of operating segments Number of Operating Segments Management core earnings fee measurement period (in years) Management Fee, Core Earnings, Measurement Period Management Fee, Core Earnings, Measurement Period Entity Central Index Key Entity Central Index Key Bank Loan Portfolio Joint Venture 1 Bank Loan Portfolio Joint Venture 1 [Member] Bank Loan Portfolio Joint Venture 1 Additional paid-in capital Additional Paid in Capital, Common Stock Equity [Abstract] Equity [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Issuance of deferred stock units (in shares) Stock Issued During Period, Shares, Deferred Stock Units Stock Issued During Period, Shares, Deferred Stock Units Securitized debt obligations, net Securitized Debt Obligation [Member] Securitized Debt Obligation Equity Method Investments, Carried At Fair Value Equity Method Investments, Carried At Fair Value [Member] Equity Method Investments, Carried At Fair Value 2026 (remaining) Long-Term Debt, Maturity, Remainder of Fiscal Year Ownership [Axis] Ownership [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Investment, Name [Axis] Investment, Name [Axis] Designated Hedges Derivatives designated as hedging instruments Designated as Hedging Instrument [Member] US Loans US Loans [Member] US Loans Foreign exchange contracts Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, before Tax Interest rate and all-in cost Debt Instrument, Basis Spread on Variable Rate Variable Rate [Domain] Variable Rate [Domain] Two Real Estate Owned Asset Two Real Estate Owned Assets [Member] Two Real Estate Owned Assets Restricted Class A Common Stock Restricted Stock [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] B-9 Term Loan B-9 Term Loan Due 2030 [Member] B-9 Term Loan Due 2030 Unrecognized compensation cost expected to be recognized over weighted average period (in years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Management and incentive fees Management and Incentive Fees Expense Statement [Line Items] Statement [Line Items] Total Assets Total assets Assets Schedule of Revenue and Expenses From Real Estate Owned Schedule Of Real Estate Owned, Income And Expenses [Table Text Block] Schedule Of Real Estate Owned, Income And Expenses Extended Maturity Extended Maturity [Member] Less: Interest and related expenses Total interest and related expenses presented in the consolidated statements of operations Interest Expense, Operating Cash and cash equivalents, book value Cash And Cash Equivalents Cash And Cash Equivalents Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Convertible notes, net Convertible Notes Convertible Debt [Member] Subsidiary of Common Parent Subsidiary of Common Parent [Member] Intangible real estate assets, net Real estate intangible assets, net Intangible Real Estate Acquired Through Foreclosure, Net Intangible Real Estate Acquired Through Foreclosure, Net Accounts receivable and other assets Accounts Receivable, Net, Current And Other Assets, Current Accounts Receivable, Net, Current And Other Assets, Current Stock-Based Incentive Plans Share-Based Payment Arrangement [Text Block] Compensation Committee Compensation Committee [Member] Compensation Committee PEO PEO [Member] 2028 Long-Term Debt, Maturity, Year Two Management base fee percentage Management and Service Fees, Rate Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount NOL limitation per annum Operating Loss Carryforwards, Limitations On Use, Annual Limitation Operating Loss Carryforwards, Limitations On Use, Annual Limitation 3.01% or more floor Financing Receivable, 3.01% Or More Floor [Member] Financing Receivable, 3.01% Or More Floor Accumulated Deficit Retained Earnings [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Percent of loans not subject to prepayment restrictions Financing Receivable, Percent Of Loans Not Subject To 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Borrowing Capacity Charge-offs Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Writeoff Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Writeoff GBP United Kingdom, Pounds Schedule of Investment in Unconsolidated Entities Equity Method Investments [Table Text Block] Financial assets Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Repurchases of class A common stock Repurchases of class A common stock Stock Repurchased During Period, Value Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Audit Committee Members Audit Committee Members [Member] Audit committee members. Schedule of Overall Statistics for Loans Receivable Portfolio Overall Statistics For Loans Receivables Portfolio [Table Text Block] Overall Statistics For Loans Receivables Portfolio [Table Text Block] Buy GBP / Sell USD Forward Foreign Exchange Contract Buy Great Britain Pound Sell United States Dollar [Member] Foreign Exchange Contract Buy Great Britain Pound Sell United States Dollar Loan principal payments held by servicer, net Loan Principal Payments Held By Servicer Loan principal payments held by servicer. Equity Method Investment [Table] Equity Method Investment [Table] Title of Individual [Axis] Title and Position [Axis] Sale of Stock [Axis] Sale of Stock [Axis] Multifamily Multifamily [Member] Unrealized loss on derivative financial instruments, net Increase (Decrease) to Net Interest Income Recognized from Derivatives Derivative, Gain (Loss) on Derivative, Net Number of loan modifications Financing Receivable, Modified, Number Of Contracts Financing Receivable, Modified, Number Of Contracts Schedule of Dividend Activity Dividends Declared [Table Text Block] Other real estate assets Other Real Estate Less: accumulated depreciation Real Estate Acquired Through Foreclosure, Accumulated Depreciation Real Estate Acquired Through Foreclosure, Accumulated Depreciation General CECL Reserves General CECL Reserves [Member] General CECL Reserves Amortization percentage Debt Instrument, Amortization Percentage Represents debt instrument amortization percentage. 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Weighted-average maximum maturity (years) Mortgage Loan On Real Estate Final Maturity Term Mortgage Loan On Real Estate Final Maturity Term Termination Date Trading Arrangement Termination Date Thereafter Lessor, Operating Lease, Payment to be Received, after Year Four Lessor, Operating Lease, Payment to be Received, after Year Four Buy AUD / Sell USD Forward Foreign Exchange Contract Buy Australian Dollar Sell United States Dollar [Member] Foreign Exchange Contract Buy Australian Dollar Sell United States Dollar Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Loan Count Count, financing provided Debt Instrument, Number Of Loans Debt Instrument, Number Of Loans Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Buy USD / Sell EUR Forward Foreign Exchange Contract Buy United States Dollar Sell European Dollar [Member] Foreign Exchange Contract Buy United States Dollar Sell European Dollar [Member] Fair Value as of Grant Date Award Grant Date Fair Value Land and land improvements Land And Site Improvements Acquired Through Foreclosure Land And Site Improvements Acquired Through Foreclosure Loss on disposition of assets Gain (Loss) on Disposition of Assets Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Share repurchase program, remaining authorized, amount Share Repurchase Program, Remaining Authorized, Amount Other operating revenue Real Estate Owned, Other Income Real Estate Owned, Other Income Arrangement Duration Trading Arrangement Duration Retail Retail Site [Member] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Interest and related expense Interest Expense, Other Income (loss) from unconsolidated entities (Income) loss from unconsolidated entities Income from unconsolidated entities Income (Loss) from Equity Method Investments Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Number of loans modified Financing Receivable, Number Of Loans Modified Financing Receivable, Number Of Loans Modified Other secured debt Secured Debt, Other Land and land improvements Land And Site Improvements Acquired Through Foreclosure, Purchase Price Allocation Land And Site Improvements Acquired Through Foreclosure, Purchase Price Allocation Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Restricted shares, vesting period (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Other real estate liabilities Other Real Estate Liabilities Other Real Estate Liabilities Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Award Type [Domain] Award Type [Domain] Fair Values Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] 2027 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One Share price (in dollars per share) Share Price Minority participation in senior term facility Subsidiary, Ownership Percentage, Noncontrolling Owner Geographical [Axis] Geographical [Axis] Restricted cash Restricted Cash Total Lessor, Operating Lease, Payment to be Received 5 Risk Rating, Five [Member] Risk Rating Five [Member]. 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Revantage Corporate Services, LLC And Revantage Global Services Europe S.à r.l. [Member] Revantage Corporate Services, LLC And Revantage Global Services Europe S.à r.l. 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