Entity Address, City or Town Other Commitment, Total Other Commitment Other commitments Interest rate swap four. Interest Rate Swap Four [Member] Interest Rate Swap Four Net Income (Loss) Available to Common Stockholders, Basic, Total Net Income Loss Available To Common Stockholders Basic Numerator for basic earnings per share Fair Value Disclosures [Abstract] Earnings Per Share [Abstract] Level 1 Fair Value Inputs Level1 [Member] Fair Value, Net Asset (Liability), Total Fair Value Net Asset Liability Net assets, end of period Pharmaceuticals. Pharmaceuticals [Member] Pharmaceuticals Human Resource Support Services. Human Resource Support Services [Member] Human Resource Support Services Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases Purchases or originations U.S. Federal Tax Domestic Tax Authority [Member] Tax refund from operating loss carryback to previous tax years Tax Refund from Operating Loss Carryback to Previous Tax Years Tax refund from operating loss carryback to previous tax years. Ibis Intermediate Co. Ibis Intermediate Co [Member] Ibis Intermediate Co. Percentage of all pre-incentive fee net investment income after catch-up achieved. Percentage Of All Pre Incentive Fee Net Investment Income After Catch Up Achieved Percentage of all pre-Incentive Fee net investment income Net Cash Provided By Used In Financing Activities [Abstract] Cash Flows from Financing Activities Value of debt converted Debt Conversion, Original Debt, Amount Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Line of credit, outstanding amount Long-Term Line of Credit Long-Term Line of Credit, Total Amendment Flag Investments at amortized cost Investment Owned At Cost Investment at amortized cost Subsequent Event Type [Domain] Line Of Credit Facility Interest Rate During Period Interest amount Deferred tax liability pertaining to unrealized gains on investment Deferred Tax Liability Pertaining to Unrealized Gains Related to Investments Deferred tax liability pertaining to unrealized gains related to investments. Bear OpCo, LLC. Bear Op Co L L C [Member] Bear OpCo, LLC CrunchTime Information Systems, Inc. CrunchTime Information Systems, Inc [Member] CrunchTime Information Systems, Inc. Total return based on market value Total Return Based On Market Value. Total Return Based On Market Value Document Quarterly Report Debt Instrument [Table] Debt Instrument [Table] Payments for Repurchase of Common Stock Purchases of treasury stock Total Dividends declared during the period. Dividends Declared During The Period Dividends declared during the period Revolver. Revolver [Member] Revolver Earnings Per Share Policy [Text Block] Earnings Per Share Statement [Table] Statement [Table] Banyan Software Holdings, LLC Banyan Software Holdings LLC [Member] Banyan Software Holdings LLC. Change in accounting principle, accounting standards update, immaterial effect Change In Accounting Principle Accounting Standards Update Immaterial Effect Lithium Technologies, LLC. Lithium Technologies L L C [Member] Lithium Technologies, LLC LIBOR London Interbank Offered Rate L I B O R [Member] Preferred Stock, Shares Outstanding, Ending Balance Preferred Stock, Shares Outstanding, Beginning Balance Preferred Stock Shares Outstanding Preferred stock, shares outstanding Original issue discount, net of accretion Original issue discount, net of accretion. Original Issue Discount Net Of Accretion Adjustment in carrying value result from hedge accounting Gain (loss) on fair value effective hedge Derivative, Fair Value Hedge, Included in Effectiveness, Gain (Loss) Net realized gains losses on investments and foreign currency translation. Net Realized Gains Losses on Investments and Foreign Currency Translation Total net realized gains (losses) Net realized gains (losses) on investments and foreign currency transactions Future Realized Capital Gains Prior to April 1, 2014 Future Realized Capital Gains Prior to April First Two Thousand Fourteen [Member] Future realized capital gains prior to April first two thousand fourteen. Percentage of all remaining pre-incentive fee net investment income quarterly. Percentage Of All Remaining Pre Incentive Fee Net Investment Income Quarterly Percentage of all remaining pre-Incentive Fee net investment income quarterly Income Tax Authority [Domain] Payments of Dividends, Total Payments Of Dividends Dividends paid to stockholders Percentage of pre-incentive fee net investment income payable after hurdle rate reached and catch-up achieved. Percentage Of Pre Incentive Fee Net Investment Income Payable After Hurdle Rate Reached And Catch Up Achieved Percentage of pre-Incentive Fee net investment income payable in any quarter Ability to Raise Additional Capital Due to Regulation Governance On BDC [Member] Ability to Raise Additional Capital Due to Regulation Governance On BDC [Member] Debt Policy [Text Block] Debt Issuance Costs Cumulative Effect Period Of Adoption Adjustment [Member] Cumulative Effect, Period of Adoption, Adjustment Carlstar Group, LLC. Carlstar Group L L C [Member] Carlstar Group, LLC Base dividend. Base Dividend [Member] Base Liabilities And Stockholders Equity Total Liabilities and Net Assets Treasury Stock Acquired, Average Cost Per Share Weighted average share price Investment Company Expense Ratio Before Incentive Allocation Ratio of net expenses to average net assets ForeScout Technologies, Inc. ForeScout Technologies, Inc. Fore Scout Technologies Inc [Member] Schedule Of Derivative Instruments [Text Block] Summary of Amounts Paid and Received on Interest Rate Swap Transactions, Excluding Upfront Fees Un-realized investment gains (losses). Un Realized Investment Gains Losses [Abstract] Net change in unrealized gains (losses): Change in Accounting Principle, Accounting Standards Update, Adopted [true false] Pledged Status [Domain] Pledged Status PageUp People, Ltd. Page Up People Ltd [Member] PageUp People, Ltd. Measurement Input Discount Rate [Member] Discount Rate Lucidworks, Inc. Lucidworks Inc [Member] Lucidworks, Inc. Entity Incorporation, State or Country Code Income Statement [Abstract] Investment owed on principal amount outstanding and accrued interest make whole amount Investment Owed On Principal Amount Outstanding And Accrued Interest Make Whole Amount. Investment Owed On Principal Amount Outstanding And Accrued Interest Special dividend. Special Dividend [Member] Special Borrow money which magnifies potential for gain or loss and increases risk of investing. Borrow Money Which Magnifies Potential for Gain or Loss and Increases Risk of Investing [Member] Adjustment for interest expense and deferred financing costs incentive fee and excise tax net. Adjustment For Interest Expense And Deferred Financing Costs Incentive Fee And Excise Tax Net Adjustment for interest expense and deferred financing costs on 2022 Convertible Notes, incentive fee and excise tax, net Sale Of Stock Name Of Transaction [Domain] Sale of Stock Structured Credit Investments Structured Credit Investments [Member] Structured credit investments. Fair Value Disclosure Of Asset And Liability Not Measured At Fair Value [Table] Fair Value Disclosure Of Asset And Liability Not Measured At Fair Value [Table] Interest Expense, Total Interest Expense Interest Asset valuation waterfall. Asset Valuation Waterfall [Member] Asset Valuation Waterfall Investment Company Realized And Unrealized Gain Loss On Investment And Foreign Currency Total Net Unrealized and Realized Gains (Losses) Summary of Dividends Declared Dividends Declared [Table Text Block] Preferred Stock Shares Authorized Preferred stock, shares authorized Revolving Credit Facility Maturity on January 31, 2025 [Member] Revolving Credit Facility Maturity on January 31, 2025 Revolving credit facility maturity on January 31, 2025. Hornetsecurity Holding GmbH Hornetsecurity Holding GMBH Member Hornetsecurity Holding GMBH. Treasury Stock, Shares, Total Treasury Stock Shares Treasury stock, shares Percentage of weighted cumulative realized capital gains less realized capital losses and unrealized capital losses through March 31, 2014 hurdle rate. Percentage of Weighted Cumulative Realized Capital Gains Less Realized Capital Losses and Unrealized Capital Losses Through March 31 2014 Hurdle Rate Percentage of weighted cumulative realized capital gains less cumulative realized capital losses and unrealized capital losses Increase (decrease) in additional paid in capital Increase Decrease in Additional Paid in Capital Increase decrease in additional paid in capital. Schedule of Components of Interest Expense Schedule Of Components Of Interest Expense [Table Text Block] Schedule of components of interest expense. Cumulative Effect Period Of Adoption [Axis] Cumulative Effect, Period of Adoption Variable Rate [Axis] Variable Rate Delayed draw. Delayed Draw [Member] Delayed Draw Entity Small Business Line Of Credit Facility Interest Rate At Period End Line of credit facility, base rate percentage Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] Equity Offering Expenses Equity Offering Expenses [Policy Text Block] Equity offering expenses. Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Table] Increase decrease in incentive fees on net capital gains accrued to affiliate. Increase Decrease In Incentive Fees On Net Capital Gains Accrued To Affiliate Incentive fees on net capital gains accrued to affiliate Investment Type Categorization [Member] Investments Increase (Decrease) in Other Operating Liabilities, Total Increase Decrease In Other Operating Liabilities Other liabilities Denominator for basic weighted average shares Weighted Average Number of Shares Outstanding, Basic, Total Weighted average shares of common stock outstanding-basic Denominator for basic weighted average shares Debt Related Commitment Fees And Debt Issuance Costs Commitment fees City Area Code Investment Company, Redemption Fee, Per Share Repurchase of common stock Repurchase of common stock Schedule Of Debt Table [Text Block] Schedule of Debt Obligations Incremental Common Shares Attributable To Conversion Of Debt Securities Adjustment for dilutive effect of 2022 Convertible Notes Issuance of common stock, net of offering costs Investment Company Distribution To Shareholders Per Share Line Of Credit Facility Unused Capacity Commitment Fee Percentage Line of credit facility, undrawn amount percentage Northeast. Northeast [Member] United States - Northeast Disco Parent, Inc. Disco Parent Inc [Member] Disco parent Inc. Fair value measurement with unobservable inputs reconciliation recurring basis asset paid-in-kind interest. Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Paid In Kind Interest Paid-in-kind interest Increase Decrease In Due From Affiliates Current Payable to affiliate Business services. Business Services [Member] Business Services Liabilities Total Liabilities Automotive. Automotive [Member] Automotive Document Period End Date Ability to enter into transactions with affiliates is restricted. Ability to Enter into Transactions with Affiliates is Restricted [Member] Noninterest Expense Directors Fees Directors’ fees AUSTRALIA Australia Risks associated with changes in interest rates. Risks Associated With Changes In Interest Rates [Member] Risks Associated with Changes in Interest Rates [Member] Deferred tax liability pertaining to net operating losses and unrealized gains on investment Deferred Tax Liability Pertaining to Net Operating Losses and Unrealized Gains Related to Investments Deferred tax liability pertaining to net operating losses and unrealized gains related to investments. Debt Securities, Available-for-Sale, Amortized Cost, Total Available For Sale Debt Securities Amortized Cost Basis Amortized Cost Insurance Insurance [Member] Insurance. Debt Conversion Converted Instrument Shares Issued1 Debt conversion, shares Issued Date Declared Dividends Payable Date Declared Day Month And Year Dividends date declared Range [Axis] Statistical Measurement Long-Term Debt, Weighted Average Interest Rate, over Time Weighted average interest rate Fair value measurement with unobservable inputs reconciliation recurring basis asset net amortization of discount on securities. Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Net Amortization Of Discount On Securities Net amortization of discount on securities Schedule of Component of Carrying Value of Convertible Notes and Interest Rate Schedule Of Component Of Carrying Value Of Convertible Notes and Interest Rate [Table Text Block] Schedule of component of carrying value of convertible notes and interest rate. Related Party Transactions By Related Party [Axis] Related Party Assets Total Assets Investments in and advances to affiliates, interest income. Investments in and Advances to Affiliates, Interest Income Interest Income Earnings per share basic and diluted line items. Earnings Per Share Basic And Diluted [Line Items] Earnings Per Share Basic And Diluted [Line Items] Derivative Contract Type [Domain] Derivative Contract Germany GERMANY Stock issued upon conversion of convertible notes, shares Stock Issued During Period, Shares, Conversion of Convertible Securities Conversion of convertible notes, Shares Increase in net assets resulting from operations Investment Company Net Assets From Operations Increase Decrease Increase in Net Assets Resulting from Operations Derivative [Line Items] Derivative [Line Items] Percentage of pre incentive fee net investment income hurdle rate quarterly. Percentage Of Pre Incentive Fee Net Investment Income Hurdle Rate Quarterly Percentage of hurdle rate Earnings Per Share, Diluted, Total Earnings Per Share Diluted Earnings per common share-diluted Net realized and unrealized gain (loss) Investment Company Gain Loss On Investment Per Share Alpha Midco, Inc. Alpha Midco Inc [Member] Alpha Midco Inc. IntelePeer Holdings, Inc. Intele Peer Holdings Inc [Member] IntelePeer Holdings, Inc. Hotel, Gaming and Leisure. Hotel Gaming And Leisure [Member] Hotel, Gaming and Leisure Schedule of Commitments To Fund Investments In Current Portfolio Companies Schedule Of Commitments To Fund Investments In Current Portfolio Companies [Table Text Block] Schedule of commitments to fund investments in current portfolio companies. Dividends declared from distributable earnings Dividends, Total Dividends Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] Pledged Status [Axis] Pledged Status Entity Address, Postal Zip Code Percentage of excess pre-incentive fee net investment income, quarterly after catch-up achieved. Percentage Of Pre Incentive Fee Net Investment Income Quarterly After Catch Up Achieved Percentage of excess pre-Incentive Fee net investment income quarterly Net change in unrealized (gains) losses on interest rate swaps Interest rate swaps Unrealized gains (losses) on derivatives Unrealized Gain Loss On Derivatives Interest rate swap one. Interest Rate Swap One [Member] Interest Rate Swap One Net realized (gains) losses on foreign currency transactions. Net Realized (Gains) Losses on Foreign Currency Transactions Net realized (gains) losses on foreign currency transactions Earnings Per Share Basic [Abstract] Earnings per common share-basic Document Fiscal Period Focus Stock repurchase program period Stock Repurchase Program, Period in Force Trading Securities Debt Debt investments Restricted Cash, Total Restricted Cash Restricted cash Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Text Block] Organization and Basis of Presentation Summary of tax basis components of distributable earnings Summary Of Tax Basis Components Of Distributable Earnings [Table Text Block] Summary of tax basis components of distributable earnings. Revolving Credit Facility [Member] Revolving Credit Facility Preferred Stock Value Preferred stock, $0.01 par value; 100,000,000 shares authorized; no shares issued and outstanding BlueSnap, Inc. Blue Snap Inc [Member] BlueSnap, Inc. Derivative [Table] Derivative [Table] Investment Income Interest Interest from investments Interest Income Interest rate swap three. Interest Rate Swap Three [Member] Interest Rate Swap Three Tango Management Consulting, LLC. Tango Management Consulting L L C [Member] Tango Management Consulting, LLC Other Nonoperating Income Other income Other Income Net Cash Provided By Used In Financing Activities Net Cash Provided by (Used in) Financing Activities Interest rate swaps. Interest Rate Swaps Interest rate swaps Related Party Transaction Selling General And Administrative Expenses From Transactions With Related Party Expenses incurred Notes Payable, Total Notes Payable Outstanding Principal Investment Owned At Fair Value Fair Value, Ending balance Fair Value, Beginning balance Total investments at fair value Statement Of Financial Position [Abstract] Entity File Number Investment Company Financial Highlights Table [Text Block] Summary Of Financial Highlights Scenario Unspecified [Domain] Scenario Shares issued Stock Issued During Period Shares Dividend Reinvestment Plan Stock issued in connection with dividend reinvestment plan, Shares Statement Of Cash Flows [Abstract] Valuation Technique [Domain] Valuation Approach and Technique Tax reclassification of stockholders' equity in accordance with GAAP Tax reclassification of stockholders' equity. Tax Reclassification Of Stockholders Equity Debt conversion principal amount. Debt Conversion Principal Amount Debt conversion principal amount Segment Geographical [Domain] Geographical Range [Member] Statistical Measurement Statement Of Stockholders Equity [Abstract] Subsidiary Sale Of Stock [Axis] Sale of Stock Dividends [Abstract] Amortization Of Debt Discount Premium Amortization of discount on debt Accretion of original issue discount South. South [Member] United States - South Obligor Group [Member] Obligor Group Percentage of non-qualifying assets. Percentage Of Non Qualifying Assets Percentage of non-qualifying assets Incentive Fee Expense Incentive fees Percentage of weighted cumulative realized capital gains less cumulative realized capital losses and unrealized capital losses. Percentage Of Weighted Cumulative Realized Capital Gains Less Cumulative Realized Capital Losses And Unrealized Capital Losses Percentage of weighted cumulative realized capital gains less cumulative realized capital losses and unrealized capital losses Realized Investment Gains Losses [Abstract] Realized gains (losses): Fair value of securities as percentage of net assets in percentage Fair Value Of Securities As Percentage Of Net Assets In Percentage Fair value of securities as percentage of net assets in percentage Subsequent Events [Abstract] Fair Value Disclosures [Text Block] Fair Value of Financial Instruments Two thousand twenty four notes. Two Thousand Twenty Four Notes [Member] 2024 Notes Retail and Consumer Products. Retail And Consumer Products [Member] Retail and Consumer Products Cash proceeds from issuance of common stock, net of underwriting fees and offering costs Proceeds From Issuance Of Common Stock Proceeds from issuance of common stock, net of offering and underwriting costs Investment, Identifier [Axis] TRP Assets, LLC. T R P Assets L L C [Member] TRP Assets, LLC Debt Instrument, Increase (Decrease), Net, Total Debt Instrument Increase Decrease For Period Net Increase (decrease) in carrying value of notes Incentive fees on net capital gains. Incentive Fees On Net Capital Gains Incentive fees on net capital gains Ratio Of Indebtedness To Net Capital1 Asset coverage ratio Fair value of securities as percentage of net assets amount Fair Value Of Securities As Percentage Of Net Assets Amount Fair value of securities as percentage of net assets amount. Unfunded Loan Commitment [Member] Unfunded Loan Commitments Derivative, fair value Derivative, Fair Value, Net, Total Derivative Fair Value Of Derivative Net Percentage of management fee in excess of annual rate on gross assets. Percentage Of Management Fee In Excess Of Annual Rate On Gross Assets Percentage of management fee in excess of annual rate on gross assets Net unrealized gains on investments Net Unrealized Gains (Losses) on Investments Net unrealized gains (losses) on investments. Line of credit facility maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Discounted Cash Flow Model Valuation Technique, Discounted Cash Flow [Member] Preferred Stock Par Or Stated Value Per Share Preferred stock, par value Investment, shares Investment Owned Balance Shares Derivative notional amount held during period. Derivative Notional Amount Held during Period Notional Amount Two thousand twenty two convertible notes member. Two Thousand Twenty Two Convertible Notes [Member] 2022 Convertible Notes Incentive fees accrued related to expense (reversal) capital gains fees. Incentive Fees Accrued Related To Expense (Reversal) Capital Gains Fees Incentive fees accrued related to expense (reversal) of capital gains fees OutSystems Luxco SARL Outsystems Luxco [Member] Outsystems Luxco. Other temporary differences Other Temporary Differences Other temporary differences. Credit Facility [Domain] Credit Facility Subsequent Events [Text Block] Subsequent Events No Longer Designated As Instruments Not Designated As Hedging Instrument Nondesignated [Member] Weighted Average Number Of Diluted Shares Outstanding Denominator for diluted weighted average shares Weighted average shares of common stock outstanding-diluted Proceeds from Short-Term Debt, Total Proceeds From Short Term Debt Borrowings on debt Derivative Liability Collateral Right To Reclaim Cash Offset Cash collateral Credit Facility [Axis] Credit Facility Reference Rate Investment Reference Rate Investment reference rate. Internet Services. Internet Services [Member] Internet Services Taxable Income Taxable Income Taxable income. General and Administrative Expense [Member] Other General and Administrative Expenses Equity investment Equity Securities, FV-NI Equity Securities, FV-NI, Total Current Fiscal Year End Date Investment Type [Axis] Investment Type Equity Securities By Industry [Axis] Industry Sector Interest rate swap six. Interest Rate Swap Six [Member] Interest Rate Swap Six Payments For Hedge Investing Activities Paid Derivative Instruments And Hedging Activities Disclosure [Abstract] Maturity Date Derivative maturity date Derivative Maturity Dates Transfers And Servicing Of Financial Instruments Types Of Financial Instruments [Domain] Financial Instruments Fair Value Disclosure Asset And Liability Not Measured At Fair Value [Line Items] Fair Value Disclosure Asset And Liability Not Measured At Fair Value [Line Items] Structured credit investments Structured Credit Investments Structured credit investments. Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations Cash, Cash Equivalents, and Restricted Cash, End of Period Cash, cash equivalents, and restricted cash, beginning of period Revolving Credit Facility Maturity on April 23, 2027 [Member] Revolving Credit Facility Maturity on April 23, 2027 Revolving credit facility maturity on April 23, 2027. Entity Address, Address Line One Incentive fees realized and payable to advisor. Incentive Fees Realized And Payable To Advisor Incentive fees realized and payable to advisor IRGSE Holding Corp. I R G S E Holding Corp [Member] IRGSE Holding Corp. Incentive fees on net investment income payable to affiliate. Incentive Fees On Net Investment Income Payable To Affiliate Incentive fees on net investment income payable to affiliate Changes in Fair Value of Investments Using Level 3 Inputs Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Text Block] Undistributed net investment income - tax basis Undistributed Net Investment Income - Tax Basis Undistributed net investment income - tax basis. Supplemental Cash Flow Information [Abstract] Supplemental Information: Investment Policy [Text Block] Investments at Fair Value Debt and Equity Securities, Unrealized Gain (Loss), Total Debt And Equity Securities Unrealized Gain Loss Net Unrealized Gain (Loss) Number of investment | Investment Number of Investments Number of investments. Income Tax Expense (Benefit), Total Income Tax Expense Benefit Income taxes, including excise taxes Investment Interest Rate Interest Rate Investments in and Advances to Affiliates, at Fair Value, Gross Reductions Gross Reductions Ordinary Income Ordinary Income Ordinary income. Two thousand twenty three notes. Two Thousand Twenty Three Notes [Member] 2023 Notes Income Taxes Income Tax Disclosure [Text Block] Preferred Stock Shares Issued Preferred stock, shares issued Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 Net realized gains (losses) Income Tax Disclosure [Abstract] Netwrix Corp. Netwrix Corp [Member] Netwrix Corp. Change In Accounting Principle Accounting Standards Update Adoption Date Change in accounting principle, accounting standards update, adoption date Net investment income Investment Company Investment Income Loss Per Share Manufacturing Manufacturing [Member] Manufacturing. Percentage of excess pre-incentive fee net investment income for immediate preceding calendar quarter. Percentage Of Excess Pre Incentive Fee Net Investment Income For Immediate Preceding Calendar Quarter Percentage of excess pre-incentive fee net investment income for immediate preceding calendar quarter Adviser. Adviser [Member] Adviser Investment percent of net assets Investment Owned Percent Of Net Assets Percentage of Net Assets Net Asset Value Per Share Net Asset Value, End of Period Net asset value, beginning of period Net Asset Value Per Share Non-controlled, non-affiliated investments. Non Controlled Non Affiliated Investments [Member] Non-controlled, Non-affiliated Investments Clinicient, Inc. Clinicient Inc [Member] Clinicient, Inc. Value of investment declines, management fee and incentive fee will be payable to adviser. Value of Investment Declines, Management Fee and Incentive Fee will be payable to Adviser [Member] Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Hierarchy and NAV Conversion of Stock, Amount Converted Common stock issued in settlement of convertible notes during the period Risks Associated with Conflicts of Interest. Risks Associated with Conflicts of Interest [Member] Equity [Abstract] Total Investments Fair Value Disclosure Net Investments fair value disclosure net. Increase decrease in incentive fees on net investment income payable to affiliate. Increase Decrease In Incentive Fees On Net Investment Income Payable To Affiliate Incentive fees on net investment income payable to affiliate Stated interest rate Debt Instrument Interest Rate Stated Percentage Debt instrument, interest rate Related Party [Domain] Related Party Additional paid-in capital Additional Paid in Capital, Common Stock BCTO Ace Purchaser, Inc. BCTO Ace Purchaser, Inc. B C T O Ace Purchaser Inc [Member] Statement Scenario [Axis] Scenario Entity Filer Category Percentage of current market price per share Current Market Price Per Share Percentage Current market price per share percentage. Oil, Gas and Consumable Fuels. Oil Gas And Consumable Fuels [Member] Oil, Gas and Consumable Fuels Summary of Industry Composition of Investments at Fair Value Summary Of Industry Composition Of Investments At Fair Value [Table Text Block] Summary of industry composition of investments at fair value. Significant Accounting Policies [Table] Significant accounting policies. Operating Expenses Total expenses Entity Current Reporting Status Net expense for federal excise tax Net Expense For Federal Excise Tax Net expense for federal excise tax. DaySmart Holdings, LLC. Day Smart Holdings L L C [Member] DaySmart Holdings, LLC Capital gains accrue following March 31, 2014. Capital Gains Accrue Following March Thirty First Two Thousand Fourteen [Member] Capital Gains Accrue Following March 31, 2014 Mezzanine debt investments. Mezzanine Debt Investments [Member] Mezzanine Debt Investments Net Assets Stockholders' Equity Note Disclosure [Text Block] Earnings Per Share Diluted [Abstract] Earnings per common share-diluted Stockholders Equity Ending balance Beginning balance Stockholders' equity Total Net Assets Net investment income Net Investment Income Investment Income, Net Income Approach Valuation Technique [Member] Income Approach Base Rate Base Rate [Member] Undistributed net realized gains - tax basis Undistributed Net Realized Gains (Losses) Tax Basis Undistributed net realized gains (losses) tax basis. Entity Tax Identification Number Income Statement Location [Axis] Income Statement Location Common stock, $0.01 par value; 400,000,000 shares authorized, 82,416,115 and 82,053,537 shares issued, respectively; and 81,751,865 and 81,389,287 shares outstanding, respectively Common Stock Value Retained Earnings (Accumulated Deficit), Total Retained Earnings Accumulated Deficit Distributable earnings Cumulative Effect Period Of Adoption [Domain] Cumulative Effect, Period of Adoption Management Fee Payable Management fees payable to affiliate Statement Equity Components [Axis] Equity Components Percentage of excess catch-up provision for pre-incentive fee net investment income. Percentage Of Excess Catch Up Provision For Pre Incentive Fee Net Investment Income Percentage of excess catch-up provision for pre-Incentive Fee net investment income Derivative, Gain (Loss) on Derivative, Net, Total Derivative Gain Loss On Derivative Net Change in Unrealized Gains / (Losses) Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net Deferred financing costs and original issue discounts Consolidated Entities [Domain] Consolidated Entities Investments owned estimated cost basis Investments Owned Estimated Cost Basis Investments owned estimated cost basis. Accounting Standards Update [Domain] Cash And Cash Equivalents Policy [Text Block] Cash and Cash Equivalents Indebtedness could adversely affect business financial conditions or results of operations. Indebtedness could Adversely Affect Business Financial Conditions or Results of Operations [Member] Minimum percentage of voting securities in investment portfolio. Minimum Percentage Of Voting Securities In Investment Portfolio Minimum percentage of voting securities 2023 Notes [Member] Twenty Twenty Three Notes [Member] Twenty twenty three notes. Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Balance, End of Period Balance, beginning of period Net expense for federal excise tax and other taxes Net Expense For Federal Excise Tax And Other Taxes Net expense for U.S. federal excise tax and other taxes Entity Emerging Growth Company Related Party Transaction [Axis] Related Party Transaction Operating Expenses [Abstract] Expenses Project44, Inc. Project44 Inc [Member] Project44, Inc. Interest Expense Debt Interest expense Total Interest Expense Debt instrument, description of variable rate basis Debt Instrument Description Of Variable Rate Basis Reference Rate and Spread Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Sale Proceeds Record Date Dividends Payable Date Of Record Day Month And Year Dividends record date PrimeRevenue, Inc. Prime Revenue Inc [Member] PrimeRevenue, Inc. CANADA Canada Line of credit facility, stated maturity date. Line Of Credit Facility Stated Maturity Date Line of credit facility, stated maturity date Luxembourg LUXEMBOURG Dividends declared from net investment income Dividends Declared From Net Investment Income Per Share. Dividends Declared From Net Investment Income Per Share Schedule Of Stock By Class [Table] Schedule Of Stock By Class [Table] Letter of Credit [Member] Letter of Credit Repayments of Convertible Debt Conversion of convertible notes 2022 Convertible Notes [Member] Twenty Twenty Two Convertible Notes [Member] Twenty twenty two convertible notes. Debt Securities Available For Sale [Table] Debt Securities Available For Sale [Table] Agreement termination period, without penalty. Agreement Termination Period Without Penalty Agreement termination period Dividends Payable [Table] Dividends Payable [Table] Document Transition Report Non-controlled, affiliated investments. Non Controlled Affiliated Investments [Member] Non-controlled, Affiliated Investments West. West [Member] United States - West Nonoperating Income Expense Total Investment Income Commitments And Contingencies Disclosure [Text Block] Commitments and Contingencies Line of credit facility, extended date. Line Of Credit Facility Extended Date Line of credit facility, extended date Percentage of net proceeds of sale of equity interests. Percentage Of Net Proceeds Of Sale Of Equity Interests Percentage of net proceeds of sale of equity interests Entity Common Stock, Shares Outstanding Amortization Of Financing Costs Amortization of deferred financing costs Increase (decrease) in distributable earnings Increase Decrease in Distributable Earnings Increase decrease in distributable earnings. Net Expense. Net Expense Net Expenses Weighted Average Weighted Average [Member] Investment advisory agreement. Investment Advisory Agreement [Member] Investment Advisory Agreement American Achievement, Corp. American Achievement Corp [Member] American Achievement Corp Investments in and Advances to Affiliates, at Fair Value Fair Value, Ending balance Fair Value, Beginning balance Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings [Text Block] Net Change in Unrealized Gains or Losses on Investments for Which Level 3 Inputs were Used in Determining Fair Value Interest rate swap ten. Interest Rate Swap Ten [Member] Interest Rate Swap Ten Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis Table [Text Block] Fair Value Measurements of Investments Additional Paid In Capital [Member] Paid in Capital in Excess of Par Supplemental dividend. Supplemental Dividend [Member] Supplemental Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Table] Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Table] Two thousand twenty three and twenty four and twenty six notes. Two Thousand Twenty Three And Twenty Four And Twenty Six Notes [Member] 2023 Notes, 2024 Notes and 2026 Notes Line Of Credit Facility Expiration Date1 Line of credit facility, expiration date Destiny Solutions Parent Holding Company. Destiny Solutions Parent Holding Company [Member] Destiny Solutions Parent Holding Company ASU 2022-06 Accounting Standards Update 2022-06 [Member] Accounting standards update 2022-06. Proceeds from settlements of interest rate swaps excluding upfront fees. Proceeds From Settlements Of Interest Rate Swaps Excluding Upfront Fees Proceeds from settlements of interest rate swaps excluding upfront fees Fair Value of Level 3 Investments at Fair Value Significant Unobservable Inputs Used in Valuations Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques Table [Text Block] Entity Registrant Name Summary of reconciliation increase in net assets Summary Of Reconciliation Increase In Net Assets [Table Text Block] Summary of reconciliation increase in net assets. Cash and cash equivalents (restricted cash of $16,162 and $15,437, respectively) Cash and Cash Equivalents, at Carrying Value, Total Cash And Cash Equivalents At Carrying Value Investment Company Realized And Unrealized Gain Loss On Investment And Foreign Currency [Abstract] Unrealized and Realized Gains (Losses) Earnings Per Share [Text Block] Earnings per Share Reimbursement of Transaction-Related Expenses Reimbursement Of Transaction Related Expenses [Policy Text Block] Reimbursement of transaction-related expenses. Elysian Finco Ltd. Elysian Finco Ltd [Member] Elysian Finco Ltd. Repayments of Short-Term Debt, Total Repayments Of Short Term Debt Repayments on debt Debt Instrument Maturity Date Debt instrument, maturity date Percentage of investments at fair value. Percentage Of Investments At Fair Value Investment fair value percentage Market Approach Valuation Technique [Member] Market Multiple Statement [Line Items] Statement [Line Items] Dividends. Dividends [Text Block] Dividends Chemicals. Chemicals [Member] Chemicals Interest rate swap twelve. Interest Rate Swap Twelve [Member] Interest Rate Swap Twelve Interest and Dividend Income Recognition Interest and Dividend Income Recognition [Policy Text Block] Interest and dividend income recognition. Title of 12(b) Security Common Stock Common Stock [Member] Common Shares Notional amount of interest rate swap Notional Amount Notional value Net Cash Provided By Used In Operating Activities [Abstract] Cash Flows from Operating Activities Interest rate swap eight. Interest Rate Swap Eight [Member] Interest Rate Swap Eight Equity Component [Domain] Equity Component Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest Net Investment Income Before Income Taxes Entity Address, State or Province Statement Geographical [Axis] Geographical Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect Document Type Interest Paid Net Interest paid during the period Investment company settlement of convertible notes per share Investment Company Settlement of Convertible Notes Per Share Settlement of 2022 Convertible Notes Avalara, Inc Avalara, Inc [Member] Avalara, Inc. UNITED STATES United States Percentage of management fee calculated on gross assets. Percentage Of Management Fee Calculated On Gross Assets Percentage of management fee on gross assets Entity Shell Company Financial and Derivative Instruments Derivatives, Policy [Policy Text Block] Percentage of ordinary income qualified as interest related dividend exempt from US withholding tax applicable to non-US shareholder Percentage of Ordinary Income Qualified as Interest Related Dividend Exempt from Domestic Withholding Tax Applicable to Foreign Shareholder Percentage of ordinary income qualified as interest related dividend exempt from domestic withholding tax applicable to foreign shareholder. Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Minimum percentage of investment company taxable income distribute to stockholders in each taxable year to qualify as RIC. Minimum Percentage Of Investment Company Taxable Income Distribute To Stockholders In Each Taxable Year To Qualify As R I C Minimum percentage of investment company taxable income distribute to stockholders in each taxable year to qualify as RIC Investments in and advances to affiliates at fair value net change in unrealized gain (loss). Investments in and Advances to Affiliates, at Fair Value, Net Change in Unrealized Gain (Loss) Net Change in Unrealized Gain/(Loss) Payments of Financing Costs, Total Payments Of Financing Costs Deferred financing costs Financing Receivable Recorded Investment By Class Of Financing Receivable [Axis] Class of Financing Receivable Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss Net change in unrealized gains (losses) Gain loss form adjustment of Paid-in-kind interest. Gain Loss form Adjustment of Paid-in-kind Interest Paid-in-kind interest Loss Contingencies [Line Items] Loss Contingencies [Line Items] Security Exchange Name Fair value of an effective hedge Fair value of an effective hedge. Fair Value Of An Effective Hedge Class Of Stock [Line Items] Class Of Stock [Line Items] Excess amount carried forward inclusive of dividends payable Excess Amount Carried Forward Inclusive of Dividends Payable Excess amount carried forward Inclusive of dividends payable. Significant Accounting Policies [Text Block] Significant Accounting Policies Nondeductible federal excise tax percentage. Nondeductible Federal Excise Tax Percentage Nondeductible U.S. federal excise tax percentage Transportation. Transportation [Member] Transportation Net Cash Provided By Used In Operating Activities Net Cash Provided by (Used in) Operating Activities Purchases and originations of investments, net. Purchases And Originations Of Investments Net Purchases and originations of investments, net Transfers within Level 3 Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Within Level 3 Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers within level 3. Investment, due date Investment due date. Investment Due Date Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements Repayments / redemptions Commitments And Contingencies Disclosure [Abstract] Estimated gross unrealized loss on tax cost investment Estimated Gross Unrealized Loss on Tax Cost Investment Estimated gross unrealized loss on tax cost investment. Repayments on investments Repayments on investments. Repayments On Investments Repayments on investments Debt investments Fair Value Alternative Investment NORWAY Norway Unrealized loss on investments. Unrealized Loss On Investments Gross unrealized losses Percentage of pre-incentive fee net investment income, annualized after catch-up achieved. Percentage Of Pre Incentive Fee Net Investment Income Annualized After Catch Up Achieved Percentage of pre-Incentive Fee net investment income annualized Recent Accounting Standards and Regulatory Updates New Accounting Pronouncements Policy Policy [Text Block] Management fee waiver hurdle. Management Fee Waiver Hurdle Percentage of asset coverage Common Stock, Shares, Outstanding, Ending Balance Common Stock, Shares, Outstanding, Beginning Balance Common Stock Shares Outstanding Common shares, outstanding Gain on extinguishment of debt Gain (Loss) on Extinguishment of Debt Gain (Loss) on Extinguishment of Debt, Total Accretion Amortization Of Discounts And Premiums Investments Net amortization of discount on investments Over Allotment Option [Member] Overallotment Option Debt Disclosure [Text Block] Debt Level 2 Fair Value Inputs Level2 [Member] Debt Securities, Available-for-Sale, Total Available For Sale Securities Debt Securities Fair Value Leverage waiver. Leverage Waiver [Member] Leverage Waiver Partnership/Membership interest of ownership Partnership Interest Ownership Percentage Partnership interest ownership percentage. Remaining investments Investments Investments, Total Commitments And Contingencies Commitments and contingencies (Note 8) Healthcare Sector [Member] Healthcare Common stock, shares issued Common Stock Shares Issued Common shares, issued Derivative Instruments And Hedging Activities Disclosure [Text Block] Derivatives Controlled, Affiliated Investments Investment, Affiliated Issuer, Controlled [Member] Liabilities [Abstract] Liabilities Edge Bidco B.V. Edge Bidco B V [Member] Edge Bidco B.V. Variable Rate [Domain] Variable Rate Minimum [Member] Minimum Hedging Designation [Axis] Hedging Designation Controlled, affiliated investments. Controlled Affiliated Investments [Member] Controlled, Affiliated Investments Investments in and advances to affiliates at fair value net realized gain loss. Investments in and Advances to Affiliates, at Fair Value, Realized Gain (Loss) Realized Gain/(Loss) Investment Company Financial Highlights [Abstract] Swap settlement. Swap Settlement Swap settlement ASG II, LLC. ASG II, LLC [Member] ASG II, LLC BTRS Holdings, Inc. BtrsHolding Inc BTRS Holding Inc. [Member] BTRS Holding Inc. [Member] Stock Issued During Period Value Dividend Reinvestment Plan Stock issued in connection with dividend reinvestment plan Tax cost of investments Tax Cost of Investments Tax cost of investments. Accounting Standards Update [Axis] Neuintel, LLC. Neuintel L L C [Member] Neuintel, LLC Percentage of minimum qualifying assets to purchase non-qualifying assets. Percentage Of Minimum Qualifying Assets To Purchase Non Qualifying Assets Percentage of minimum qualifying assets to purchase non qualifying assets Realized gains (losses) on derivatives Gain (Loss) on Sale of Derivatives Net realized (gains) on interest rate swaps Interest rate swaps Debt Instrument [Axis] Debt Instrument Stockholders Equity [Abstract] Net Assets Treasury Stock [Member] Treasury Stock EMS Linq, Inc. EMS Linq, Inc. E M S Linq Inc [Member] Management fees waived (Note 3) Management Fee Waived Management fee waived. Entity Address, Address Line Two PrimePay Intermediate, LLC. Prime Pay Intermediate L L C [Member] PrimePay Intermediate, LLC Second-lien debt investments. Second Lien Debt Investments [Member] Second-lien Debt Investments Investments in and advances to affiliates, other income. Investments in and Advances to Affiliates, Other Income Other Income Incentive fees on net investment income. Incentive Fees On Net Investment Income Incentive fees on net investment income Incentive fees realized and payable to advisor Foreign Currency Transactions And Translations Policy [Text Block] Foreign Currency Investment Company Financial Highlights [Text Block] Financial Highlights Dividends [Domain] Dividends Payments for settlements of interest rate swaps excluding upfront fees. Payments For Settlements Of Interest Rate Swaps Excluding Upfront Fees Payments for settlements of interest rate swaps excluding upfront fees Subsequent Event [Member] Subsequent Event Interest rate swap two. Interest Rate Swap Two [Member] Interest Rate Swap Two Per Share Market Value At End Period. Per Share Market Value At End Period Per share market value at end of period Net realized (gains) losses on investments Realized Investment Gains (Losses), Total Realized Investment Gains Losses Realized gains (losses) on investments Realized loss Related Party Transaction [Domain] Related Party Transaction Deferred tax asset Deferred Tax Assets, Gross Deferred Tax Assets, Gross, Total Loss Contingencies [Table] Loss Contingencies [Table] Investments at fair value. Investments At Fair Value [Text Block] Investments at Fair Value Net unrealized (gains) losses on investments Net unrealized (gains) losses on investments Net change in unrealized gains (losses) on investments and foreign currency translation. Net Change In Unrealized Gains Losses On Investments And Foreign Currency Translation Total net change in unrealized gains (losses) Net change in unrealized gain (losses) on investments and foreign currency translation Financing Receivable Recorded Investment Class Of Financing Receivable [Domain] Class of Financing Receivable Investment Income Dividend Dividend income Dividend Income Nonoperating Income Expense [Abstract] Income Fair Value of Company's 2023 Notes, 2024 Notes and 2026 Notes Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Entity Central Index Key Purchase commitment to fund investment. Purchase Commitment To Fund Investment Total Portfolio Company Commitments Accounting Policies [Abstract] Management and incentive fees waived Management and Incentive Fees Waived Management and incentive fees waived. Investments Debt And Equity Securities [Abstract] Percentage of management fee in excess of quarter rate on gross assets Percentage of Management Fee in Excess of Quarter Rate on Gross Assets Percentage of management fee in excess of quarter rate on gross assets. Other book-tax differences Other Book-tax Differences Other book-tax differences. Office Products. Office Products [Member] Office Products Schedule Of Available For Sale Securities [Line Items] Schedule Of Available For Sale Securities [Line Items] Interest Receivable Interest receivable Communications. Communications [Member] Communications Hedging Designation [Domain] Hedging Designation Estimated gross unrealized gains on tax cost investment Estimated Gross Unrealized Gains on Tax Cost Investment Estimated gross unrealized gains on tax cost investment. Dividends Payable Current And Noncurrent Dividends payable Percentage of excess pre-incentive fee net investment income payable after hurdle rate reached and catch-up achieved. Percentage Of Excess Pre Incentive Fee Net Investment Income Payable After Hurdle Rate Reached And Catch Up Achieved Percentage of excess pre-Incentive Fee net investment income Percentage of capital gains from April 1, 2024 hurdle rate. Percentage of Capital Gains From April 1 2024 Hurdle Rate Percentage of incentive fee rate Measurement Input Type [Domain] Measurement Input Type Organization Consolidation And Presentation Of Financial Statements [Abstract] Deferred financing costs Debt Issuance Costs, Net, Total Deferred Finance Costs Net Deferred financing costs Forecast [Member] Forecast Debt Instrument Convertible Conversion Price1 Debt instrument, conversion price ExtraHop Networks, Inc. Extra Hop Networks Inc [Member] ExtraHop Networks Inc. Equity and Other Investments Equity and other investments. Equity And Other Investments [Member] Investment Company Investment Income Loss Ratio Ratio of net investment income to average net assets Adjustments to reconcile increase (decrease) in net assets resulting from operations to net cash provided by (used in) operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Distributable Earnings Retained Earnings [Member] Realized capital gains accrued beginning April 1, 2014. Realized Capital Gains Accrued Beginning April First Two Thousand Fourteen [Member] Realized Capital Gains Accrued Beginning April 1, 2014 Additional aggregate principal amount. Additional Aggregate Principal Amount Additional aggregate principal amount Axonify, Inc. Axonify Inc [Member] Axonify, Inc. Investment, Issuer Affiliation [Domain] Designated As Hedging Instrument [Member] Designated As Hedging Instrument Dividends [Axis] Dividends Measurement Input Type [Axis] Measurement Input Type Equity Securities Industry [Member] Industry Sector Passport Labs, Inc. Passport Labs Inc [Member] Passport Labs, Inc. Offsetting Assets and Liabilities Offsetting Assets And Liabilities [Policy Text Block] Offsetting assets and liabilities. Dividends to Common Stockholders Dividends [Policy Text Block] Dividends. Interest rate swap seven. Interest Rate Swap Seven [Member] Interest Rate Swap Seven Entity Interactive Data Current First-lien debt investments. First Lien Debt Investments [Member] First-lien Debt Investments Asset Pledged As Collateral [Member] Asset Pledged as Collateral Other General And Administrative Expense Other general and administrative Related Party Transactions Disclosure [Text Block] Agreements and Related Party Transactions Letters Of Credit Outstanding Amount Issuance of letters of credit Murchison Oil and Gas, LLC. Murchison Oil and Gas, LLC [Member] Murchison Oil and Gas, LLC Cash Flow Noncash Investing And Financing Activities Disclosure [Abstract] Non-Cash Financing Activities: Related Party Transactions [Abstract] Percentage of pre-incentive fee net investment income payable quarterly. Percentage Of Pre Incentive Fee Net Investment Income Payable Quarterly Percentage of total pre-Incentive fee net investment income payable quarterly Other Income Other Income [Policy Text Block] Other income. Workwell Acquisition Co. Workwell Acquisition Co [Member] Workwell Acquisition Co. Proceeds from issuance of debt, net of underwriting discount, offering costs and original issue discount Proceeds From Unsecured Notes Payable Local Phone Number Equity and other investments. Equity And Other Investments Equity and other investments Erling Lux Bidco SARL. Erling Lux Bidco SARL [Member] Erling Lux Bidco SARL Erling Lux Bidco Sarl Biohaven Pharmaceuticals, Inc. Biohaven Pharmaceuticals Inc [Member] Biohaven Pharmaceuticals, Inc. Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Computation of Basic and Diluted Earnings Per Common Share Bayshore Intermediate #2, L.P. Bayshore Intermediate2 L P [Member] Bayshore Intermediate #2, LP Net Payments For Proceeds From Hedge Investing Activities Net Debt Disclosure [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Interest Rate Swap [Member] Interest Rate Swap Investment, par Investment Owned, Face Amount Income Taxes, Including Excise Taxes Income Taxes Including Excise Taxes [Policy Text Block] Income taxes, including excise taxes. Consolidated Entities [Axis] Consolidated Entities Interest rate swap eleven. Interest Rate Swap Eleven [Member] Interest Rate Swap Eleven AvidXchange, Inc. Avid Xchange Inc [Member] AvidXchange, Inc. Realized capital gains accrued prior to March 31, 2014. Realized Capital Gains Accrued Prior To March Thirty First Two Thousand Fourteen [Member] Realized Capital Gains Accrued Prior to March 31, 2014 Income Statement Location [Domain] Income Statement Location Treasury Stock, Value, Acquired, Cost Method Total cost Purchases of treasury stock WideOrbit, Inc. Wide Orbit Inc [Member] WideOrbit, Inc. Incentive fee rate Percentage of incentive fee rate. Percentage Of Incentive Fee Rate Debt (net of deferred financing costs of $16,533 and $17,760, respectively) Carrying Value Carrying value of debt Outstanding debt Shares Outstanding Ending balance,Shares Beginning balance, Shares Shares Outstanding, End of Period Amount Available Line Of Credit Facility Remaining Borrowing Capacity Line of credit facility, remaining borrowing capacity Increase Decrease In Prepaid Deferred Expense And Other Assets Prepaid expenses and other assets Investment owned initial acquisition date. Investment Owned Initial Acquisition Date Initial Acquisition Date Debt Instrument Name [Domain] Debt Instrument, Name Document Fiscal Year Focus Deferred organization costs Deferred Organization Costs Deferred organization costs. Extinguishment Of Debt Amount Extinguishment of debt, amount Interest Rate Derivatives, at Fair Value, Net, Total Interest Rate Derivatives At Fair Value Net Fair Market Value Fair market value Legislation allows to incur additional leverage. Legislation Allows to Incur Additional Leverage [Member] Two thousand twenty six notes. Two Thousand Twenty Six Notes [Member] 2026 Notes Investment Company, Expense Ratio, Voluntary Fee Waiver Ratio of net expenses to average net asset, excluding waiver Interest receivable Increase Decrease In Accrued Interest Receivable Net Interest receivable Earnings Per Share, Basic, Total Earnings Per Share Basic Earnings per common share-basic Income Taxes Paid Excise and other taxes paid during the period Summary of Shares Newly Issued to Shareholders Who Have Not Opted Out of Dividend Reinvestment Plan Summary of Shares Newly Issued to Shareholders Who Have Not Opted Out of Dividend Reinvestment Plan [Table Text Block] Summary of shares newly issued to shareholders who have not opted out of dividend reinvestment plan. Assets [Abstract] Assets Total investments at fair value Investments Fair Value Disclosure Organization Organization [Policy Text Block] Organization policy. Other income for tax purposes, not book Other Income For Tax Purposes, Not Book Other income for tax purposes, not book. Treasury stock at cost; 664,250 and 664,250 shares held, respectively Treasury Stock, Value, Total Treasury Stock Value Treasury stock at cost; 476,586 and 296,044 shares held, respectively Shares issued, price per share Shares Issued, Price Per Share Debt Instrument Face Amount Aggregate principal amount Aggregate Principal Amount Committed Schedule of earnings per share basic and diluted table. Schedule Of Earnings Per Share Basic And Diluted [Table] Schedule Of Earnings Per Share Basic And Diluted [Table] Total Interest Expense Interest And Debt Expense Total Interest Expense Financial Instrument [Axis] Financial Instrument Other expenses not currently deductible Other Expenses Not Currently Deductible Other expenses not currently deductible. Investment, Issuer Affiliation [Axis] Interest Rate, PIK Investment, Interest Rate, Paid in Kind Cordance Operations, LLC. Cordance Operations LLC [Member] Cordance Operations, LLC Dividends Payable Amount Per Share Dividend per Share Education. Education [Member] Education Summary of Geographic Composition of Investments at Fair Value Summary Of Geographic Composition Of Investments At Fair Value [Table Text Block] Summary of geographic composition of investments at fair value. Interest rate swap five. Interest Rate Swap Five [Member] Interest Rate Swap Five ReliaQuest Holdings, LLC. Relia Quest Holdings L L C [Member] ReliaQuest Holdings, LLC Asset coverage percentage. Asset Coverage Percentage Asset coverage percentage LeanTaaS Holdings, Inc. LeanTaaS Holdings Inc [Member] LeanTaaS Holdings, Inc. Income Tax Authority [Axis] Valuation Technique [Axis] Valuation Approach and Technique Deferred tax asset offset by valuation allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance, Total Increase (decrease) in net assets resulting from operations Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total Profit Loss Net change in unrealized (gains) losses on foreign currency transactions Foreign Currency Transaction Gain Loss Unrealized Translation of other assets and liabilities in foreign currencies Midwest. Midwest [Member] United States - Midwest Total return based on market value with reinvestment of dividends Total Return Based On Market Value With Reinvestment Of Dividends. Total Return Based On Market Value With Reinvestment Of Dividends EDB Parent, LLC. E D B Parent L L C [Member] EDB Parent, LLC Increase decrease in interest receivable paid-in-kind. Increase Decrease In Interest Receivable Paid In Kind Interest receivable paid-in-kind Stock repurchase program, expiration date Stock Repurchase Program Expiration Date Management Fee Expense Management fees Interest rate swap nine. Interest Rate Swap Nine [Member] Interest Rate Swap Nine Fair Value Measurements Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV Debt Conversion Converted Instrument Amount1 Debt instrument, principal converted amount G Treasury SS, LLC. G Treasury S S L L C [Member] G Treasury SS, LLC Total return based on net asset value Total Return Based On Net Asset Value. Total Return Based On Net Asset Value Increase Decrease In Operating Capital [Abstract] Changes in operating assets and liabilities: Related Party Transaction [Line Items] Related Party Transaction [Line Items] Administration agreement. Administration Agreement [Member] Administration Agreement Increase decrease in management fees payable to affiliate. Increase Decrease In Management Fees Payable To Affiliate Management fees payable to affiliate Dividends Payable [Line Items] Dividends Payable [Line Items] Cost model. Cost Model [Member] Cost Model Summary of tax character of shareholder distributions Summary Of Tax Character Of Shareholder Distributions [Table Text Block] Summary of tax character of shareholder distributions. Upfront (Payments) / Receipts in derivative assets and liabilities Upfront Payments Receipts In Derivative Assets And Liabilities Upfront (Payments) / Receipts Black Scholes model. Black Scholes Model [Member] Black Scholes Model Adjustments: Adjustment Adjustment Marketing Services. Marketing Services [Member] Marketing Services Foreign Currency Transaction Gain Loss Realized Foreign currency transactions Transfers Net realized (gains) losses on foreign currency transactions Unrealized gain on investments. Unrealized Gain On Investments Gross unrealized gain Investments in and Advances to Affiliates, at Fair Value, Gross Additions Gross Additions Total from operations Investment Company Investment Income Loss From Operations Per Share Total from operations Revolving Credit Facility Maturity on February 4, 2026 [Member] Revolving Credit Facility Maturity on February 4, 2026 Revolving credit facility maturity on February 4, 2026, Investment Company Incentive Fee To Average Net Assets Portfolio turnover Financial Services Sector [Member] Financial Services Dividend Payable Date To Be Paid Day Month And Year Payment Date Maximum [Member] Maximum Delayed draw and revolver. Delayed Draw And Revolver [Member] Delayed Draw & Revolver Capital Gains Long-Term Capital Gains Long-term capital gains. Employment Hero Holdings Pty Ltd. Employment Hero Holdings Pty Ltd [Member] Employment Hero Holdings Pty Ltd. Netherlands NETHERLANDS Transfers into (out of) Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net, Total Laramie Energy, LLC Laramie Energy L L C [Member] Laramie Energy LLC. Level 3 Fair Value Inputs Level3 [Member] Use Of Estimates Use of Estimates Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan Reinvestment of dividends during the period Debt Instrument, basis spread on variable rate Debt Instrument Basis Spread On Variable Rate1 Reference Rate and Spread percentage Dividends payable Dividends Payable, Current Dye & Durham Corp. Dye Durham Corp [Member] Dye & Durham Corp. Coupa Holdings, LLC Coupa Holdings L L C [Member] Coupa Holdings LLC. Cash Cash Incentive fees on net capital gains accrued to affiliate. Incentive Fees On Net Capital Gains Accrued To Affiliate Incentive fees on net capital gains accrued to affiliate Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net Assets, Beginning Balance Net Assets, Ending Balance Net Assets Total Net Assets Total Net Assets Significant Accounting Policies [Line Items] Significant accounting policies. Kyriba Corp. Kyriba Corp [Member] Kyriba Corp. Delayed Draw and Membership Interest Delayed Draw and Membership Interest [Member] Delayed Draw and Membership Interest [Member] Verdad Resources Intermediate Holdings, LLC Verdad Resources Intermediate Holdings, LLC. Verdad Resources Intermediate Holdings L L C [Member] Dividends date shares issued Dividends payable date of shares issued day month and year. Dividends Payable Date Of Shares Issued Day Month And Year Due To Affiliate Current And Noncurrent Other payables to affiliate 2024 Notes [Member] Twenty Twenty Four Notes [Member] Twenty twenty four notes. Prepaid Expense And Other Assets Prepaid expenses and other assets Investment measurement input Alternative Investment Measurement Input Principal amount of debt Debt Instrument Carrying Amount Outstanding Principal Ping Identity Holding Corp Ping Identity Corporation [Member] Ping Identity Corporation. Common Stock Shares Authorized Common shares, authorized Derivative, basis spread on variable rate Derivative, Basis Spread on Variable Rate Trading Symbol Dividend Dividends Payable, Nature Net Income Loss Available To Common Stockholders Diluted Numerator for diluted earnings per share Interest Expense [Member] Interest Expense Debt Securities Available For Sale Table [Text Block] Summary of Investments at Fair Value Interest rate swap thirteen. Interest Rate Swap Thirteen [Member] Interest Rate Swap Thirteen 2026 Notes [Member] Twenty Twenty Six Notes [Member] Twenty twenty six notes. Other Liabilities, Total Other Liabilities Other liabilities Measurement Input Comparability Adjustment [Member] Comparable Multiple Subsequent Event Type [Axis] Notes Payable Fair Value Disclosure Fair Value Line Of Credit Facility Average Outstanding Amount Average debt outstanding (in millions) Excise and other taxes paid during the period. Excise And Other Taxes Paid During The Period Excise and other taxes paid during the period Professional Fees Professional fees Fiscal Period, Policy [Policy Text Block] Fiscal Year End Total distributable earnings - book basis Distributed Earnings Proceeds From Hedge Investing Activities Received Schedule Of Related Party Transactions By Related Party [Table] Schedule Of Related Party Transactions By Related Party [Table] Number of shares repurchased Treasury Stock, Shares, Acquired Purchases of treasury stock, Shares Common stock, price per share Common Stock Par Or Stated Value Per Share Common shares, par value Proceeds from investments, net. Proceeds From Investments Net Proceeds from investments, net Total increase (decrease) in net assets Investment Company Net Asset Value Per Share Period Increase Decrease Total increase/(decrease) in net assets Other. Other [Member] Other Stock issued upon conversion of convertible notes, value Stock Issued During Period Value Conversion Of Convertible Securities Stock repurchase program, authorized amount Stock Repurchase Program, Authorized Amount Net change in unrealized (gains) losses on investments Unrealized Gain Loss On Investments Unrealized gains (losses) on investments Net Change In Unrealized Gain/(Loss) Derivative Instrument Risk [Axis] Derivative Instrument UNITED KINGDOM United Kingdom Debt Instrument [Line Items] Debt Instrument [Line Items] Tax Credit Carryforward [Line Items]