Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] February Notes [Member] February Notes Trading Arrangement: Trading Arrangement [Axis] Investment Management Agreement - Incentive Rate, Quarterly Hurdle Rate Investment Management Agreement - Incentive Rate, Quarterly Hurdle Rate [Member] Investment Management Agreement - Incentive Rate, Quarterly Hurdle Rate Maximum Maximum [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] Proceeds from termination of CSAs Proceeds From Termination Of Cost Sharing Agreement Proceeds From Termination Of Cost Sharing Agreement Interest rate extended Line Of Credit, Interest Rate Step Up Increase Pursuant To Investment Grade Conditions Line of Credit Interest Rate Increase Repurchase agreement counterparty, amount at risk Repurchase Agreement Counterparty, Amount at Risk Title of 12(b) Security Subsequent Event Subsequent Event [Member] Document Fiscal Year Focus Adjustment to Compensation, Amount Adjustment to Compensation Amount Financial Instrument [Axis] Financial Instrument [Axis] Rocade Holdings LLC Rocade Holdings LLC [Member] Rocade Holdings LLC Payable from unsettled transactions Payable, Investment, Purchase Schedule of Fair Value, Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Common stock, $0.001 par value per share (150,000,000 shares authorized, 104,706,884 shares issued and outstanding as of both June 30, 2026 and December 31, 2025) Common Stock, Value, Issued Investment Denominated in Euros Investment Denominated In Euros [Member] Investment Denominated In Euros Foreign currency transactions Net realized (gain) loss on foreign currency transactions Realized Gain (Loss), Foreign Currency Transaction, before Tax Schedule of Borrowings Outstanding Schedule of Long-Term Debt Instruments [Table Text Block] Investment Management Agreement - Incentive Rate, Annualized Hurdle Rate Investment Management Agreement - Incentive Rate, Annualized Hurdle Rate [Member] Investment Management Agreement - Incentive Rate, Annualized Hurdle Rate Line of Credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Capital Equipment Capital Equipment Capital Equipment [Member] Capital Equipment Accretion of loan origination and other fees Amortization of Deferred Loan Origination Fees, Net Derivative Instrument [Axis] Derivative Instrument [Axis] Affiliate investments Investment, Affiliated Issuer, Noncontrolled [Member] Non-Control / Non-Affiliate investments Investment, Unaffiliated Issuer [Member] Celebration Bidco, LLC Celebration Bidco, LLC [Member] Celebration Bidco, LLC Number of members Investment Company, Number of Members Contributed Investment Company, Number of Members Contributed Number of components Related Party Transaction, Number Of Components Related Party Transaction, Number Of Components Amendment Flag Metals & Mining Metals And Mining [Member] Metals And Mining Administrative fees payable Administrative Fees Payable Administrative Fees Payable Entity Common Stock, Shares Outstanding Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold [Member] Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold Investment Management Agreement - Incentive Rate, Quarterly Catch-Up Threshold Investment Management Agreement - Incentive Rate, Quarterly Catch-Up Threshold [Member] Investment Management Agreement - Incentive Rate, Quarterly Catch-Up Threshold New Portfolio Investments New Portfolio Investments [Member] New Portfolio Investments Net investment income before taxes Net Investment Income Debt Denominated In Canadian Dollars Borrowings Denominated In Canadian Dollars Under February 2019 Credit Facility [Member] Borrowings Denominated In Canadian Dollars Under February 2019 Credit Facility Investments [Domain] Investments [Domain] Biolam Group Biolam Group [Member] Biolam Group Adjustments to reconcile net increase (decrease) in net assets resulting from operations to net cash provided by (used in) operating activities: Adjustments To Reconcile Net Assets From Operations To Cash Provided by (Used in) Operating Activities [Abstract] Adjustments To Reconcile Net Assets From Operations To Cash Provided by (Used in) Operating Activities AGREEMENTS AND RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Aerospace & Defense Aerospace Sector [Member] PEO Total Compensation Amount PEO Total Compensation Amount Investment Company, Nonconsolidated Subsidiary [Axis] Investment Company, Nonconsolidated Subsidiary [Axis] Common stock par value (in dollars per share) Common Stock, Par or Stated Value Per Share Retail Retail Sector [Member] Asset Acquisition [Axis] Asset Acquisition [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Notional Amount Notional amount Derivative, Notional Amount Weighted average shares outstanding—basic (in shares) Weighted Average Number of Shares Outstanding, Basic Credit support agreements Net realized (gain) loss of CSAs Gain on credit support agreement Realized Gain (Loss) On Credit Support Agreement Realized Gain (Loss) On Credit Support Agreement Investments subject to leveling Investments Subject to Leveling [Member] Investments Subject to Leveling Interest Period Of Six Month Interest Period Of Six Month [Member] Interest Period Of Six Month Credit support agreements Net unrealized (appreciation) depreciation of CSAs Unrealized Gain (Loss) On Credit Support Agreement Unrealized Gain (Loss) On Credit Support Agreement Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount MVC Credit Support Agreement - Covered Credit Losses Minimum MVC Credit Support Agreement - Covered Credit Losses Minimum [Member] MVC Credit Support Agreement - Covered Credit Losses Minimum Number of reportable segments Number of Reportable Segments September 15, 2025 - September 2028 Notes September 2028 Notes [Member] September 2028 Notes Schedule of Investments [Abstract] Schedule of Fair Value and Aggregate Unrealized Appreciation (Depreciation) Schedule of Derivative Instruments [Table Text Block] Netherlands NETHERLANDS Interest and fees receivable Increase (Decrease) in Accrued Interest Receivable, Net November 13, 2025 Credit Facility November 13, 2025 Credit Facility [Member] November 13, 2025 Credit Facility Entity Address, City or Town Construction & Building Construction And Building [Member] Construction And Building Gross Amount of Recognized Assets (Liabilities) Fair value Derivative, Fair Value, Net Barings LLC Barings LLC [Member] Barings LLC Combined weighted average debt outstanding Long-Term Debt, Average Amount Outstanding Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Total PIK income Interest and Dividend Income, Operating, Paid in Kind Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Policy Services Company, LLC Policy Services Company, LLC [Member] Policy Services Company, LLC Level 2 Fair Value, Inputs, Level 2 [Member] Gross Reductions Investments in and Advances to Affiliates, at Fair Value, Gross Reductions Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Net investment income (in dollars per share) Investment Company, Investment Income (Loss), Per Share, Basic New Barings BDC Advisory Agreement New Barings BDC Advisory Agreement - Quarterly Incentive Fee Rate [Member] New Barings BDC Advisory Agreement - Quarterly Incentive Fee Rate Commitment aggregate amount Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Interest rate, cash Investment Interest Rate Net increase (decrease) in net assets resulting from operations per share—basic and diluted (in dollars per share) Investment Company, Net Asset Value, Per Share, Period Increase (Decrease) USA UNITED STATES INVESTMENTS Schedule of Investments [Text Block] Citibank N.A. Subscription Facility Citibank N.A. Subscription Facility [Member] Citibank N.A. Subscription Facility Total dividend income Dividend Income, Operating Energy: Electricity Energy: Electricity Energy: Electricity [Member] Energy: Electricity Subsequent Event Type [Axis] Subsequent Event Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Waccamaw River, LLC Waccamaw River, LLC [Member] Waccamaw River, LLC Total operating expenses Investment Income, Investment Expense Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Amortization of deferred financing fees Amortization of Debt Issuance Costs Related Party [Axis] Related and Nonrelated Parties [Axis] Principal repayments received Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Principal Repayment Received Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Principal Repayment Received High Tech Industries High Tech Industries High Tech Industries [Member] High Tech Industries Regular quarterly dividends / distributions, declared (in dollars per share) Common Stock, Dividends, Per Share, Declared, Ordinary Common Stock, Dividends, Per Share, Declared, Ordinary Investment grade conditions Line Of Credit, Interest Rate Step Up To Increase Pursuant To Debt To Total Assets Threshold Line Of Credit, Interest Rate Step Up To Increase Pursuant To Debt To Total Assets Threshold Interest Period [Axis] Interest Period [Axis] Interest Period Total Notes Long-Term Debt Average net assets Investment Company, Average Net Assets External Credit Rating by Grouping [Domain] External Credit Rating by Grouping [Domain] Chemicals, Plastics, & Rubber Chemicals, Plastics, And Rubber [Member] Chemicals, Plastics, And Rubber Guarantor Obligations [Line Items] Guarantor Obligations [Line Items] Document Period End Date Changes in operating assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Overnight Bank Funding Rate Overnight Bank Funding Rate [Member] Overnight Bank Funding Rate Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Investment Management Agreement - Incentive Rate, Capital Gain Fee Investment Management Agreement - Incentive Rate, Capital Gain Fee [Member] Investment Management Agreement - Incentive Rate, Capital Gain Fee Aggregate principal amount Debt Instrument, Face Amount Net assets at end of period Net Assets Security Exchange Name Foreign currencies (cost of $18,490 and $14,922 as of June 30, 2026 and December 31, 2025, respectively) Cash and Cash Equivalent, Held in Foreign Currency Effective interest rate Debt Instrument, Interest Rate, Effective Percentage Federal Housing Administration (“FHA”) loans Federal Housing Administration (“FHA”) Loans [Member] Federal Housing Administration (“FHA”) Loans Recovery Rate Measurement Input, Recovery Rate [Member] Measurement Input, Recovery Rate Distributions recognized as a return of capital Investment Company, Distributions Of Realized Gains Investment Company, Distributions Of Realized Gains Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Entity Shell Company Singapore SINGAPORE Schedule of Composition of Investment Portfolio at Cost And Fair Value Investment Holdings, Schedule of Investments [Table Text Block] Name Outstanding Recovery, Individual Name Dividends / distributions per share: Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Investment, interest rate, paid in kind, toggle one Investment, Interest Rate, Paid In Kind, Toggle One Investment, Interest Rate, Paid In Kind, Toggle One Services: Business Services: Business [Member] Services: Business Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Financial Guarantee Financial Guarantee [Member] Total liabilities Liabilities Trading Symbol Discount Rate Measurement Input, Discount Rate [Member] Euro Interbank Offered Rate (EURIBOR) Euro Interbank Offered Rate (EURIBOR) [Member] Euro Interbank Offered Rate (EURIBOR) Geographical [Domain] Geographical [Domain] Telecommunications Telecommunications [Member] Telecommunications 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] Loan origination fees received Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Loan Origination Fees Received Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Loan Origination Fees Received Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Company Selected Measure Name Company Selected Measure Name Schedule of Investments [Table] Schedule of Investments [Table] MMALIC MMALIC [Member] MMALIC Income Tax Disclosure [Abstract] Erste Bank And MCV Automotive Group Gmbh Erste Bank And MCV Automotive Group Gmbh [Member] Erste Bank And MCV Automotive Group Gmbh Unrealized gross depreciation Investment, Tax Basis, Unrealized Loss Company Receives Derivative, fixed interest rate Derivative, Fixed Interest Rate Recurring Fee and Other Income: Recurring Fee Income [Abstract] Recurring Fee Income Forward currency contracts Net unrealized (appreciation) depreciation on forward currency contracts Unrealized Appreciation (Depreciation) Unrealized Gain (Loss) on Derivatives Interest-earning assets, average yield Interest-Earning Assets, Average Yield Long-term debt, gross Long-Term Debt, Gross Debt Investments Debt Securities [Member] Credit Facility [Domain] Credit Facility [Domain] Related Party Transactions [Abstract] Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Single Portfolio Company Single Portfolio Company [Member] Single Portfolio Company Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Weighted average shares outstanding—diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Total dividends/distributions per share, paid (in dollars per share) Common Stock, Dividends, Per Share, Cash Paid Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Original Advisory Agreement Original Advisory Agreement - Quarterly Incentive Fee Rate [Member] Original Advisory Agreement - Quarterly Incentive Fee Rate Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Underlying Security Market Price Change Underlying Security Market Price Change, Percent Dividends Dividends Schedule of PIK Interest and Dividend Income Investment Income [Table Text Block] DERIVATIVE INSTRUMENTS Derivative Instruments and Hedging Activities Disclosure [Text Block] Previous Valuation And Technique [Axis] Previous Valuation And Technique [Axis] Previous Valuation And Technique Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income [Member] Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Interest Period [Domain] Interest Period [Domain] Interest Period [Domain] Guarantor obligations Guarantor Obligations, Current Carrying Value Interest and fees receivable Dividend and Interest Receivable Existing Portfolio Existing Portfolio [Member] Existing Portfolio Deemed contribution - CSA (in dollars per share) Investment Company, Deemed Contribution, Credit Support Agreement, Per Share Investment Company, Deemed Contribution, Credit Support Agreement, Per Share Due from related parties Other Receivables Schedule of Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Investment Company, Financial Highlights [Roll Forward] Investment Company, Financial Highlights [Roll Forward] Award Timing Predetermined Award Timing Predetermined [Flag] Sierra JV Sierra JV [Member] Sierra JV Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Debt Denominated In Euro Borrowings Denominated In Euro Under February 2019 Credit Facility [Member] Borrowings Denominated In Euro Under February 2019 Credit Facility Level 1 Fair Value, Inputs, Level 1 [Member] Investment Management Agreement - Incentive Rate, Annual Catch-Up Threshold Investment Management Agreement - Incentive Rate, Annual Catch-Up Threshold [Member] Investment Management Agreement - Incentive Rate, Annual Catch-Up Threshold MVC Automotive Group GmbH MVC Automotive Group GmbH [Member] MVC Automotive Group GmbH Series B Senior Unsecured Notes due November 2025 Series B Senior Unsecured Notes due November 2025 [Member] Series B Senior Unsecured Notes due November 2025 Investment Company, Net Assets [Roll Forward] Investment Company, Net Assets [Roll Forward] Loss on sale of investments Gain (Loss) on Sale of Investments Notional Amount to be Sold Derivative Asset, Notional Amount Investment with Previous Commitment to Provide Financing Investment With Previous Commitment To Provide Financing [Member] Investment With Previous Commitment To Provide Financing Gross Amount of Recognized Assets Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement Cash (restricted cash of $18,349 and $12,933 as of June 30, 2026 and December 31, 2025, respectively) Cash and Cash Equivalent, Not Held in Foreign Currency Ratio of net investment income to average net assets (annualized) Investment Company, Investment Income (Loss) Ratio Construction & Building Construction Sector [Member] All Executive Categories All Executive Categories [Member] Total fee and other income Total Fee and Other Income Fee And Other Income Fee And Other Income Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Investment Advisory Agreement Investment Advisory Agreement [Member] Investment Advisory Agreement [Member] Repayments of credit facility Repayments of credit facility Repayments of Long-Term Lines of Credit Fair value of long-term debt Long-Term Debt, Fair Value Asset Acquisition [Domain] Asset Acquisition [Domain] Black-Scholes Valuation Technique, Black-Scholes-Merton Model [Member] Structured products Structured Product Structured Products [Member] Structured Products Concentration Risk Type [Domain] Concentration Risk Type [Domain] Santander Bank and MVC Automotive Group GmbH Santander Bank and MVC Automotive Group GmbH [Member] Santander Bank and MVC Automotive Group GmbH Energy: Oil & Gas Energy: Oil And Gas [Member] Energy: Oil And Gas Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Excise taxes paid during the period Excise Taxes Paid Excise Taxes Paid Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Royalty Rights: Royalty [Member] Investment Company, Nonconsolidated Subsidiary [Domain] Investment Company, Nonconsolidated Subsidiary [Domain] Minimum Minimum [Member] Borrowings under credit facility Long-Term Line of Credit Investment Type [Axis] Investment Type [Axis] Expiration Date Trading Arrangement Expiration Date Liabilities: Liabilities [Abstract] Income Statement Location [Axis] Location, Statement of Income, Balance [Axis] Valuation, Unadjusted Prices From Independent Pricing Services And Independent Indicative Broker Quotes Valuation, Unadjusted Prices From Independent Pricing Services And Independent Indicative Broker Quotes [Member] Valuation, Unadjusted Prices From Independent Pricing Services And Independent Indicative Broker Quotes Healthcare & Pharmaceuticals Healthcare & Pharmaceuticals [Member] Healthcare & Pharmaceuticals Restricted cash Restricted Cash and Cash Equivalent Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Measurement input Derivative Asset, Measurement Input Affiliated Entity Affiliated Entity [Member] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] Net investment income after taxes Net investment income Investment Income, Operating, after Expense and Tax Common stock, shares authorized (in shares) Common Stock, Shares Authorized Consumer goods: Durable Consumer goods: Durable Consumer Goods: Durable [Member] Consumer Goods: Durable Prior Sierra Credit Support Agreement Covered Credit Losses Minimum Prior Sierra Credit Support Agreement Covered Credit Losses Minimum [Member] Prior Sierra Credit Support Agreement Covered Credit Losses Minimum Enterprise Value / Equity Value Measurement Input, Enterprise Value [Member] Measurement Input, Enterprise Value Aerospace & Defense Aerospace And Defense [Member] Aerospace And Defense Exercise Price Award Exercise Price Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Weighted average yield Investment Owned, Weighted Average Yield Investment Owned, Weighted Average Yield Related Party Transaction [Axis] Related Party Transaction [Axis] Yield Analysis Valuation, Yield Analysis [Member] Valuation, Yield Analysis Common stock aggregate amount Share Repurchase Program, Authorized, Amount Document Quarterly Report February 19, 2026 Program February 19, 2026 Program [Member] February 19, 2026 Program Interest Period Of One Month Interest Period Of One Month [Member] Interest Period Of One Month Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Interest Rate Swap Interest Rate Swap [Member] Input Investment Company, Investment Owned, Measurement Input BORROWINGS Debt Disclosure [Text Block] Investments, cost Cost Investment Owned, Cost Gross Additions Investments in and Advances to Affiliates, at Fair Value, Gross Additions Interest payable Interest Payable Receivable from unsettled transactions Receivable, Investment, Sale Base management fee (Note 2) Base management fee Management Fee Expense (Less: Deferred financing fees) Debt Issuance Costs, Net Reallocation of loans from revolving commitments to term loan commitments Line Of Credit Facility, Change In Reallocation Of Commitments Line Of Credit Facility, Change In Reallocation Of Commitments Open Forward Foreign Currency Contract, Identifier [Axis] Open Forward Foreign Currency Contract, Identifier [Axis] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] FINANCIAL HIGHLIGHTS Investment Company, Financial Highlights [Text Block] All Members Of Jocassee Partners LLC All Members Of Jocassee Partners LLC [Member] All Members Of Jocassee Partners LLC Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Fair value recurring basis gain (losses) Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Measurement Input Type [Domain] Measurement Input Type [Domain] Beverage, Food, & Tobacco Beverage, Food, & Tobacco Beverage, Food And Tobacco [Member] Beverage, Food And Tobacco Purchases of portfolio investments Purchases of portfolio investments Payment for Purchase, Investment, Operating Activity Foreign Exchange Contract Foreign Exchange Contract [Member] Consumer Loan Consumer Loan [Member] Adoption Date Trading Arrangement Adoption Date Fixed interest rate Debt Instrument, Interest Rate, Stated Percentage Counterparty Name [Domain] Counterparty Name [Domain] Total net assets Beginning balance Ending balance Equity, Attributable to Parent Zeppelin Bidco Limited Zeppelin Bidco Limited [Member] Zeppelin Bidco Limited Investment Denominated in Canadian Dollars Investment Denominated In Canadian Dollars [Member] Investment Denominated In Canadian Dollars Incentive management fees payable Incentive Fee Payable Non-Recurring Fee and Other Income: Non-Recurring Fee Income [Abstract] Non-Recurring Fee Income Assets: Assets [Abstract] Adjusted EBITDA Multiple Measurement Input, EBITDA Multiple [Member] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Veterans Affairs (“VA”) loans Veterans Affairs (“VA”) Loans [Member] Veterans Affairs (“VA”) Loans Eclipse Business Capital, LLC Eclipse Business Capital, LLC [Member] Eclipse Business Capital, LLC Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Insider Trading Policies and Procedures [Line Items] Investment, Issuer Affiliation [Domain] Investment, Issuer Affiliation [Domain] Interest income from cash Interest Income, Operating Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Net realized gains (losses): Net Realized Gains (Losses) [Abstract] Net Realized Gains (Losses) Investment in joint ventures Investment In Joint Ventures [Member] Investment In Joint Ventures Bank Of America Subscription Facility Bank Of America Subscription Facility [Member] Bank Of America Subscription Facility COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] February 20, 2025 Program February 20, 2025 Program [Member] February 20, 2025 Program Number of operating segments Number of Operating Segments Excise and sales taxes Excise and Sales Taxes Senior debt and 1st lien notes Senior Debt and 1st Lien Notes Debt Securities, Senior Debt and 1st Lien Notes [Member] Debt Securities, Senior Debt and 1st Lien Notes Central Index Key Applicable Rate Applicable Currency Rate [Member] Applicable Currency Rate Weighted Average Weighted Average [Member] MVC Credit Support Agreement MVC Credit Support Agreement [Member] MVC Credit Support Agreement All Adjustments to Compensation All Adjustments to Compensation [Member] Series D And Series E Senior Unsecured Notes Due February Series D And Series E Senior Unsecured Notes Due February [Member] Series D And Series E Senior Unsecured Notes Due February Schedule of Guarantor Obligations [Table] Guarantor Obligation [Table] 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] Net cash provided by (used in) operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Investment owned, weighted average yield rate Investment Owned, Weighted Average Yield Rate Investment Owned, Weighted Average Yield Rate Income Statement [Abstract] Net Assets: Equity, Attributable to Parent [Abstract] Document Transition Report Interest Period Of Three Month Interest Period Of Three Month [Member] Interest Period Of Three Month Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Schedule of Investments [Line Items] Schedule of Investments [Line Items] PIK dividend income Dividend Income, Operating, Paid in Kind Investment, Name [Axis] Investment, Name [Axis] Average loan amount Investment Company, Average Loan Amount Investment Company, Average Loan Amount Share Repurchase Program [Table] Share Repurchase Program [Table] Operating expenses: Operating Expenses [Abstract] Simulation Analysis Valuation, Simulation Analysis [Member] Valuation, Simulation Analysis Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] February 25, 2021 Series E Notes Series E Senior Unsecured Notes due February 2028 [Member] Series E Senior Unsecured Notes due February 2028 Unrealized gross appreciation Investment, Tax Basis, Unrealized Gain Sierra Senior Loan Strategy JV I LLC Sierra Senior Loan Strategy JV I LLC Sierra Senior Loan Strategy JV I LLC [Member] Sierra Senior Loan Strategy JV I LLC Net increase (decrease) in net assets resulting from operations Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax Regular quarterly dividends / distributions, paid (in dollars per share) Common Stock, Dividends, Per Share, Paid , Ordinary Common Stock, Dividends, Per Share, Paid , Ordinary Net unrealized appreciation (depreciation) on investments Net unrealized (appreciation) depreciation on investments Debt and Equity Securities, Unrealized Gain (Loss) New Barings BDC Advisory Agreement - Annualized Incentive Fee Rate New Barings BDC Advisory Agreement - Annualized Incentive Fee Rate [Member] New Barings BDC Advisory Agreement - Annualized Incentive Fee Rate Debt instrument, basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate SCRS South Carolina Retirement Systems Group Trust [Member] South Carolina Retirement Systems Group Trust Net realized gains (losses) on investments Debt And Equity Securities, Realized Gain (Loss) Before Distributions Debt And Equity Securities, Realized Gain (Loss) Before Distributions Basis spread on variable rate Investment, Basis Spread, Variable Rate City Area Code Variable Rate [Domain] Variable Rate [Domain] Investment owned, face amount Investment Owned, Face Amount Geographic Concentration Risk Geographic Concentration Risk [Member] All Individuals All Individuals [Member] SUBSEQUENT EVENTS Subsequent Events [Text Block] Investment, Issuer Name [Domain] Investment, Issuer Name [Domain] Volatility Measurement Input, Price Volatility [Member] Schedule of Balances of Unused Commitments to Extend Financing Schedule of Loss Contingencies by Contingency [Table Text Block] Cash dividends / distributions paid Payments of Dividends Name Forgone Recovery, Individual Name Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Investment, interest, current yield Investment Owned, Interest, Current Yield Investment Owned, Interest, Current Yield Net realized (gain) loss on investments Debt and Equity Securities, Realized Gain (Loss) Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Derivate asset, cost Derivate Asset, Cost Derivate Asset, Cost Net Asset Approach Valuation Technique, Net Asset Approach [Member] Valuation Technique, Net Asset Approach Statement [Line Items] Statement [Line Items] Total assets Assets Investment restructuring Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Restructuring Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Restructuring Entity [Domain] November 5, 2020 - Series C Notes Series C Senior Unsecured Notes due November 2027 [Member] Series C Senior Unsecured Notes due November 2027 Interest and other financing fees Interest Expense, Operating Market value at end of period (in dollars per share) Investment Company, Market Value, Per Share Industry Sector [Axis] Industry Sector [Axis] Series A Senior Unsecured Notes due August 2025 Series A Senior Unsecured Notes due August 2025 [Member] Series A Senior Unsecured Notes due August 2025 Eclipse Business Capital Holdings LLC Eclipse Business Capital Holdings LLC [Member] Eclipse Business Capital Holdings LLC Asset Volatility Measurement Input, Asset Volatility [Member] Measurement Input, Asset Volatility PEO PEO [Member] Base management fee, percent Management and Service Fees, Rate Principal Amount Investment Owned, Balance, Principal Amount Debt Securities, Structured Product Position Debt Securities, Structured Product Position [Member] Debt Securities, Structured Product Position Gross Amount of Recognized Liabilities Derivative Asset, Subject to Master Netting Arrangement, Liability Offset Cost of investments, income tax purposes Investment, Tax Basis, Cost PIK interest income as a % of investment income Interest Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Interest Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Media: Broadcasting & Subscription Media: Broadcasting And Subscription [Member] Media: Broadcasting And Subscription Subsequent Event Type [Domain] Subsequent Event Type [Domain] Time Until Exit (years) Measurement Input, Time Until Exit [Member] Measurement Input, Time Until Exit Net Asset Approach Net Asset Approach [Member] Net Asset Approach Total Distributable Earnings (Loss) Retained Earnings [Member] Combined weighted average interest rate Long-Term Debt, Weighted Average Interest Rate, over Time Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold [Member] Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold Investment Company [Abstract] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Total increase (decrease) from investment operations (in dollars per share) Investment Company, Investment Income (Loss) from Operations, Per Share Schedule of Fair Value Measurement Inputs and Valuation Techniques Schedule of Significant Unobservable Inputs used in Valuation Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Common stock, shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Shares outstanding at end of period (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Net investment income per share—diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Net cash provided by (used in) financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Control investments Investment, Affiliated Issuer, Controlled [Member] Total Shareholder Return Amount Total Shareholder Return Amount Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Incentive management fees (Note 2) Incentive management fees Incentive Fee Expense Total interest income Interest Income, Operating, Paid in Cash Investment Management Agreement Investment Management Agreement [Member] Investment Management Agreement Media: Diversified & Production Media: Diversified And Production [Member] Media: Diversified And Production Total PIK income as a % of investment income Interest And Dividend Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Interest And Dividend Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Chemicals, Plastics, & Rubber Chemicals Sector [Member] Borrowings under credit facility Proceeds from Long-Term Lines of Credit Special dividends / distributions, paid (in dollars per share) Common Stock, Dividends, Per Share, Paid, Special Common Stock, Dividends, Per Share, Paid, Special Market Yield Measurement Input, Market Yield [Member] Measurement Input, Market Yield Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Containers, Packaging, & Glass Containers, Packaging And Glass [Member] Containers, Packaging And Glass Percentage of unused portion of credit facility, greater than two-third of commitments Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Financial Instruments [Domain] Financial Instruments [Domain] Total return Investment Company, Total Return, Market Value All Members Of Thompson Rivers LLC All Members Of Thompson Rivers LLC [Member] All Members Of Thompson Rivers LLC Debt instrument, credit spread adjustment Debt Instrument, Credit Spread Adjustment Debt Instrument, Credit Spread Adjustment Derivative assets Value Derivative Asset Purchases of shares in repurchase plan Stock Repurchased During Period, Value Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Share Repurchase Program [Line Items] Share Repurchase Program [Line Items] Underlying Securities Award Underlying Securities Amount Interest payable Increase (Decrease) in Interest Payable, Net Proceeds from sales of investments / return of capital Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales MassMutual Ascend Life Insurance Company MassMutual Ascend Life Insurance Company [Member] MassMutual Ascend Life Insurance Company Foreign Currency Derivatives [Abstract] Foreign Currency Derivatives [Abstract] Schedule of Financial Highlights Investment Company, Financial Highlights [Table Text Block] Thompson Rivers LLC Thompson Rivers LLC [Member] Thompson Rivers LLC Schedule of Investment Portfolio Investment Company, Nonconsolidated Subsidiary, Summarized Financial Information [Table Text Block] Subordinated debt and 2nd lien notes Subordinated Debt and 2nd Lien Notes Debt Securities, Subordinated Debt and 2nd Lien Notes [Member] Debt Securities, Subordinated Debt and 2nd Lien Notes Investment, Issuer Name [Axis] Investment, Issuer Name [Axis] Screen Rate Screen Rate [Member] Screen Rate Industry Concentration Risk Industry Concentration Risk [Member] Industry Concentration Risk Payment-in-kind interest / dividends Payment In-Kind Interest And Dividends Payment In-Kind Interest And Dividends EMI Porta Holdco LLC EMI Porta Holdco LLC [Member] EMI Porta Holdco LLC Acceleration of unamortized loan origination fees Acceleration of Unamortized Loan Origination Fees Acceleration of Unamortized Loan Origination Fees Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Table] Schedule of Equity Method Investments [Table] Equity Method Investment [Table] Cash Cash [Member] February 21, 2019 February 2019 Credit Facility [Member] February 2019 Credit Facility Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Current Fiscal Year End Date Investment owned, balance (in shares) Investment Owned, Balance, Shares Previous Valuation And Technique [Domain] Previous Valuation And Technique [Domain] Previous Valuation And Technique [Domain] Transportation: Consumer Transportation: Consumer [Member] Transportation: Consumer Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Derivative [Line Items] Derivative [Line Items] Related Party Transaction [Domain] Related Party Transaction [Domain] Number of investments entered into Investment Owned, Number Of Investments Entered Into Investment Owned, Number Of Investments Entered Into Skyvault Holdings LLC Skyvault Holdings LLC [Member] Skyvault Holdings LLC Subscription Facility Subscription Facility [Member] Subscription Facility Purchases of shares in repurchase plan (in shares) Shares of common stock repurchased (in shares) Stock Repurchased During Period, Shares Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Total dividends / distributions per share, declared (in dollars per share) Quarterly dividend declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Net realized gains (losses) and unrealized appreciation (depreciation) on investments, credit support agreements, foreign currency transactions and forward currency contracts Gain (Loss), Investment, Derivative, and Foreign Currency Transaction Price Change, Operating, before Tax Total investments at fair value Fair Value Fair value at beginning balance Fair value at ending balance Fair value Investment Owned, Fair Value PIK dividend income as % of investment income Dividend Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Dividend Income, Operating, Paid In Kind As A Percentage Of Gross Investment Income, Operating Equity Investments Equity shares Equity Shares Equity Securities [Member] Consumer goods: Non-durable Consumer goods: Non-durable Consumer Goods: Non-Durable [Member] Consumer Goods: Non-Durable All Members Of Sierra JV All Members Of Sierra JV [Member] All 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non-cash information Noncash Financing Items [Abstract] Noncash Financing Items Total Non-Recurring Fee and Other Income Non-Recurring Fee Income Net Non-Recurring Fee Income Net One-Month Secured Overnight Financing Rate (SOFR) One-Month Secured Overnight Financing Rate (SOFR) [Member] One-Month Secured Overnight Financing Rate (SOFR) Spain SPAIN Equity Components [Axis] Equity Components [Axis] Related Party Related Party [Member] Shares of common stock repurchased, average price (in dollars per share) Stock Repurchased Purchase Program, Average Cost Per Share Stock Repurchased Purchase Program, Average Cost Per Share Net deferred tax assets, valuation allowance Deferred Tax Assets, Valuation Allowance Original Advisory Agreement - Annualized Incentive Fee Rate Original Advisory Agreement - Annualized Incentive Fee Rate [Member] Original Advisory Agreement - Annualized Incentive Fee Rate Schedule of Foreign Currency Forward Contracts Schedule of Foreign Exchange Contracts, Statement of Financial Position [Table Text Block] Special dividends / distributions, declared (in dollars per share) Common Stock, Dividends, Per Share, Declared, Special Common Stock, Dividends, Per Share, Declared, Special Entity Interactive Data Current Variable Rate [Axis] Variable Rate [Axis] Percentage of Total Portfolio, at Fair Value Investment Owned, At Fair Value [Member] Investment Owned, At Fair Value Deemed contribution - CSA Cash Flow, Noncash Investing and Financing Activities Disclosure, Deemed Contribution Credit Support Agreement Cash Flow, Noncash Investing and Financing Activities Disclosure, Deemed Contribution Credit Support Agreement Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Deferred financing fees Debt Issuance Costs, Line of Credit Arrangements, Net Entity Small Business Total Recurring Fee and Other Income Investment Company, Recurring Fee Income Investment Company, Recurring Fee Income Termination Date Trading Arrangement Termination Date February 12, 2024 - February 2029 Notes February 2029 Notes [Member] February 2029 Notes Termination and cancellation agreement, payment Termination And Cancellation Agreement, Payment Termination And Cancellation Agreement, Payment Germany GERMANY Subsequent Events [Abstract] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Expected proceeds from termination Derivative, Expected Proceeds Derivative, Expected Proceeds Repayments received / sales of portfolio investments Proceeds from Disposition of Investment, Operating Activity Debt issuance costs, financing fees Debt Issuance Costs, Line of Credit Arrangements, Gross Document Type Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net Expected Recovery 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Consumer Services: Consumer [Member] Services: Consumer Entity Address, Postal Zip Code Entity Registrant Name Net unrealized appreciation (depreciation) on investments / CSAs / foreign currency transactions / forward currency contracts (in dollars per share) Investment Company, Unrealized Gain (Loss) on Investment, Per Share Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Investment Denominated in New Zealand Dollars Investment Denominated In New Zealand Dollars [Member] Investment Denominated In New Zealand Dollars Coastal Marina Holdings, LLC Coastal Marina Holdings, LLC [Member] Coastal Marina Holdings, LLC Commitments and contingencies (Note 7) Commitments and Contingencies Royalty rights Royalty Rights Royalty Rights [Member] Royalty Rights Royalty income Royalty Income, Operating Royalty Income, Operating Containers, Packaging, & Glass Container and Packaging Sector [Member] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Schedule of Fee and Other Income Schedule Of Fee Income [Table Text Block] Schedule Of Fee Income Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Investment Denominated in Norwegian Krone Investment Denominated In Norwegian Krone [Member] Investment Denominated In Norwegian Krone Distributions of net investment income Investment Company, Dividend Distribution Total payment-in-kind interest income PIK interest income Interest Income, Operating, Paid in Kind Executive Category: Executive Category [Axis] February 25, 2021 Series D Notes Series D Senior Unsecured Notes due February 2026 [Member] Series D Senior Unsecured Notes due February 2026 Amortization of loan origination fees Amortization Of Loan Origination Fees Amortization Of Loan Origination Fees Counterparty Name [Axis] Counterparty Name [Axis] Australia AUSTRALIA Sierra Merger Sierra Merger [Member] Sierra Merger All Member Of Waccamaw River LLC All Member Of Waccamaw River LLC [Member] All Member Of Waccamaw River LLC Austria AUSTRIA Amount of Unrealized Gain (Loss) Unrealized Gain (Loss), Derivative and Foreign Currency Transaction Price Change, Operating, before Tax Investment, Excluding Short Term Investment, with Previous Commitment to Provide Financing Investment, Excluding Short Term Investment, With Previous Commitment To Provide Financing [Member] Investment, Excluding Short Term Investment, With Previous Commitment To Provide Financing All Award Types Award Type [Domain] Net realized gain (loss) on investments / CSAs / foreign currency transactions / forward currency contracts (in dollars per share) Investment Company, Realized Gain (Loss) on Investment, Per Share Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Sierra Credit Support Agreement Covered Credit Losses Minimum New Sierra Credit Support Agreement Covered Credit Losses Minimum [Member] New Sierra Credit Support Agreement Covered Credit Losses Minimum November 23, 2021 - November 2026 Notes November 2026 Notes [Member] November 2026 Notes Revenue Multiple Measurement Input, Revenue Multiple [Member] Fair Value, Inputs, Level 3 Level 3 Fair Value, Inputs, Level 3 [Member] Supplemental Information: Supplemental Cash Flow Information [Abstract] Long-Term Investments Long-Term Investments [Member] Long-Term Investments Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities PEO Name PEO Name Belgium BELGIUM Expected Recovery Measurement Input, Expected Recovery [Member] Measurement Input, Expected Recovery Geographical [Axis] Geographical [Axis] Utilities: Oil & Gas Utilities: Oil And Gas [Member] Utilities: Oil And Gas Portfolio Company Investment Risk Portfolio Company Investment Risk [Member] Portfolio Company Investment Risk Investment Management Agreement - Incentive Rate, Realized Capital Gains Investment Management Agreement - Incentive Rate, Realized Capital Gains [Member] Investment Management Agreement - Incentive Rate, Realized Capital Gains Line of credit facility commitment aggregate value Line of Credit Facility, Accordion Feature, Aggregate Limit Line of credit facility, accordion feature, increase limit, subject to certain conditions by obtaining additional commitments from existing and/or new lenders. Investment, Issuer Affiliation [Axis] Investment, Issuer Affiliation [Axis] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Legal Entity [Axis] Amount of Interest or Dividends Credited to Income Interest and Dividend Income, Securities, Operating Prepaid expenses and other assets Prepaid Expense and Other Assets Notes payable (net of deferred financing fees) Notes Payable Cash and foreign currencies, beginning of period Cash and foreign currencies, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Base management fees payable Management Fee Payable Ireland IRELAND Entity Incorporation, State or Country Code Base Rate Base Rate [Member] Investment Management Agreement - Incentive Rate, Cumulative Pre-Incentive Fee Net Return Investment Management Agreement - Incentive Rate, Cumulative Pre-Incentive Fee Net Return [Member] Investment Management Agreement - Incentive Rate, Cumulative Pre-Incentive Fee Net Return Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] External Credit Rating, Investment Grade External Credit Rating, Investment Grade [Member] Incentive fee, percent Management and Service Fees, Incentive Rate Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Investment Funds & Vehicles Investment Funds And Vehicles [Member] Investment Funds And Vehicles Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Investment Denominated in Danish Kroner Investment Denominated In Danish Kroner [Member] Investment Denominated In Danish Kroner Media: Advertising, Printing, & Publishing Media: Advertising, Printing And Publishing [Member] Media: Advertising, Printing And Publishing Debt Instrument [Axis] Subsequent Event [Table] Subsequent Event [Table] Ownership percent Equity Method Investment, Ownership Percentage Investment Denominated in Swedish Krone Investment Denominated In Swedish Krone [Member] Investment Denominated In Swedish Krone Number of portfolio companies Number Of Non-Accrual Portfolio Companies Number Of Non-Accrual Portfolio Companies Utilities: Electric Utilities: Electric [Member] Utilities: Electric Related party transaction amount (up to) Related Party Transaction, Amounts of Transaction Investment, Name [Domain] Investment, Name [Domain] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Net investment income per share—basic (in dollars per share) Earnings Per Share, Basic Measurement Input Type [Axis] Measurement Input Type [Axis] Net unrealized appreciation (depreciation): Investment Owned, Recognized Unrealized Appreciation (Depreciation), Net [Abstract] Investment Owned, Recognized Unrealized Appreciation (Depreciation), Net Number of investments Investment Owned, Number Of Investments Investment Owned, Number Of Investments Purchases of shares in repurchase plan Payments for Repurchase of Common Stock Statistical Measurement [Axis] Statistical Measurement [Axis] Ginnie Mae Early Buyout Loans Ginnie Mae Early Buyout Loans [Member] Ginnie Mae Early Buyout Loans Insider Trading Arrangements [Line Items] Base management fee, percent Management and Service Fees, Base Rate Bank of America N.A., Bank of America N.A., [Member] Bank of America N.A., Award Type Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Total contributed capital Investment Company, Accumulated Contributed Capital Investment Company, Accumulated Contributed Capital Unrealized depreciation Investment, Tax Basis, Unrealized Gain (Loss) Net unrealized appreciation (depreciation) Net unrealized (depreciation) appreciation on investments / CSAs / foreign currency transactions / forward currency contracts Unrealized Gain (Loss), Investment, Derivative, and Foreign Currency Transaction Price Change, Operating, before Tax Total distributable earnings (loss) Retained Earnings (Accumulated Deficit) Hong Kong HONG KONG Investment company, remaining average life to maturity Investment Company, Remaining Average Life To Maturity Investment Company, Remaining Average Life To Maturity New Sierra Credit Support Agreement New Sierra Credit Support Agreement [Member] New Sierra Credit Support Agreement Number of portfolio companies covered under credit support agreement Number Of Portfolio Companies Covered Under Credit Support Agreement Number Of Portfolio Companies Covered Under Credit Support Agreement Healthcare & Pharmaceuticals Healthcare And Pharmaceuticals [Member] Healthcare And Pharmaceuticals Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Committed investment amount Total unfunded commitments Investment Company, Financial Support to Investee Contractually Required, Not Provided, Amount Hotel, Gaming, & Leisure Hotel, Gaming And Leisure [Member] Hotel, Gaming And Leisure External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] ORGANIZATION, BUSINESS AND BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Cover [Abstract] Line of credit, repayment period after maturity Line Of Credit, 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Dollars Borrowings Denominated In U.S Dollars under February 2019 Credit Facility [Member] Borrowings Denominated In U.S Dollars under February 2019 Credit Facility Employee Stock Option Share-Based Payment Arrangement, Option [Member] New investments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Investment Denominated in Australian Dollars Investment Denominated In Australian Dollars [Member] Investment Denominated In Australian Dollars Industry Sector [Domain] Industry Sector [Domain] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Related Party [Domain] Related and Nonrelated Parties [Domain] Percentage of Total Net Assets Investment Owned, Net Assets, Percentage Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Investment Type Concentration Risk Investment Type Concentration Risk [Member] Investment Type Concentration Risk Fair Value, Asset, Recurring 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Insurance, & Real Estate Banking, Finance, Insurance, & Real Estate Banking, Finance, Insurance And Real Estate [Member] Banking, Finance, Insurance And Real Estate General and administrative expenses (Note 2) General and Administrative Expense Amount of Interest or Dividends Credited to Income Interest And Dividend Income, Securities, Operating, Including True Up Adjustment Interest And Dividend Income, Securities, Operating, Including True Up Adjustment France FRANCE Dividends / distributions paid to stockholders from net investment income (in dollars per share) Investment Company, Distribution to Shareholders, Per Share Investments with No Previous Contractual Commitment to Provide Financing Investments With No Previous Contractual Commitment To Provide Financing [Member] Investments With No Previous Contractual Commitment To Provide Financing Series B And Series C Senior Unsecured Notes Due November Series B And Series C Senior Unsecured Notes Due November [Member] Series B And Series C Senior Unsecured Notes Due November Adjustment to Compensation: Adjustment to Compensation [Axis] Net deferred tax asset Deferred Tax Assets, Investments Amended and Restated Advisory Agreement Amended and Restated Advisory Agreement [Member] Amended and Restated Advisory Agreement Term Debt Securitization Term Debt Securitization [Member] Term Debt Securitization Australian Benchmark Rate Australian Benchmark Rate [Member] Australian Benchmark Rate Share Repurchase Program [Axis] Share Repurchase Program [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] JPMorgan Chase Bank JPMorgan Chase Bank [Member] JPMorgan Chase Bank Ratio of total expenses, including loss on extinguishment of debt and provision for taxes, to average net assets (annualized) Investment Company, Expense Ratio after Incentive Allocation Debt instrument, basis spread on variable floor rate Debt Instrument, Variable Interest Rate, Floor Debt Instrument, Variable Interest Rate, Floor Prepayment fees Prepayment Fees on Advances, Net Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Name Measure Name INCOME TAXES Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Related party transaction, term Related Party Transaction, Term Related Party Transaction, Term Debt Instrument [Line Items] Debt Instrument [Line Items] MVC Private Equity Fund LP MVC Private Equity Fund LP [Member] MVC Private Equity Fund LP Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Transaction Price Measurement Input, Transaction Price [Member] Measurement Input, Transaction Price Forward currency contracts Net realized (gain) loss on forward currency contracts Gain (Loss) on Sale of Derivatives Liabilities Measurement Input, Liability [Member] Measurement Input, Liability Investment company, dividend reinvestment Investment Company, Dividend Reinvestment Investment Company, Dividend Reinvestment Additional Paid-In Capital Additional Paid-in Capital [Member] Entity Filer Category Contributed capital by related parties Investment Company, Committed Capital Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Federal Funds Purchased Federal Funds Purchased [Member] Automotive Automotive Sector [Member] Deemed contribution - CSA (See Note 2) Adjustments To Additional Paid In Capital, Deemed Contribution From Credit Support Agreement Adjustments To Additional Paid In Capital, Deemed Contribution From Credit Support Agreement Name Trading Arrangement, Individual Name Management, valuation and other fees Management, Valuation and Other Fees 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Security Holdings B.V. [Member] Security Holdings B.V. Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Transportation: Cargo Transportation: Cargo [Member] Transportation: Cargo Entity Address, Address Line Two CORRA CORRA [Member] CORRA Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Percentage of Total Portfolio, at Cost Investment Owned, At Cost [Member] Investment Owned, At Cost Total investment income Gross Investment Income, Operating Non-qualifying assets Investment Owned, Non-Qualifying Assets Investment Owned, Non-Qualifying Assets Derivative liabilities Derivative liabilities Derivative Liability Borrowings Denominated In Eurounder February 2019 Credit Facility Borrowings Denominated In Eurounder February 2019 Credit Facility [Member] Borrowings Denominated In Eurounder February 2019 Credit Facility Non-PEO NEO Non-PEO NEO [Member] Notes Senior Notes [Member] Credit Support Agreements Credit Risk Contract [Member] Entity Address, Address Line One Advisory, loan amendment and other fees Advisory, Loan Amendment And Other Fees Income (Expense) Advisory, Loan Amendment And Other Fees Income (Expense) Proceeds from issuance of debt Proceeds From Issuance Of Senior Long Term Debt, Net Proceeds From Issuance Of Senior Long Term Debt, Net Income taxes, including excise tax expense Investment Income, Operating, Tax Expense (Benefit) Derivative, variable interest rate Derivative, Variable Interest Rate Investments in and Advances to Affiliates, at Fair Value [Roll Forward] Investments in and Advances to Affiliates, at Fair Value [Roll Forward] Net realized gains (losses) Net realized gain (loss) on investments / CSAs / foreign currency transactions / forward currency contracts Realized Gain (Loss), Investment, Derivative, and Foreign Currency Transaction Price Change, Operating, before Tax Award Timing Method Award Timing Method [Text Block] Net increase (decrease) in cash and foreign currencies Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Portfolio turnover ratio (annualized) Investment Company, Portfolio Turnover Notional Amount to be Purchased Derivative Liability, Notional Amount Net increase (decrease) in net assets resulting from operations Net Income (Loss) Attributable to Parent Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Number of portfolio companies, that was on PIK non-accrual Number Of Paid-In-Kind, Partial Non-Accrual Portfolio Companies, Originated By The Company Number Of Paid-In-Kind, Partial Non-Accrual Portfolio Companies, Originated By The Company Proceeds from derivative contracts Proceeds From Derivative Instruments, Operating Activities Proceeds From Derivative Instruments, Operating Activities Discounted Cash Flow Analysis Valuation Technique, Discounted Cash Flow [Member] Black Angus Steakhouses, LLC Black Angus Steakhouses, LLC [Member] Black Angus Steakhouses, LLC Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Term of contract Derivative, Contract Term Number of portfolio companies, initiated by the company Number Of Non-Accrual Portfolio Companies, Originated By The Company Number Of Non-Accrual Portfolio Companies, Originated By The Company Pre-Incentive Fee Net Investment Income For Trailing Twelve Quarters Exceeds Catch-Up Amount Investment Management Agreement - 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