Statistical Measurement [Domain] Statistical Measurement [Domain] Investments Investment, Policy [Policy Text Block] Non-controlled/Non-affiliated Investment, Unaffiliated Issuer [Member] Diamondback Acquisition, Inc. Diamondback Acquisition, Inc. 2 [Member] Diamondback Acquisition, Inc. 2 Award Timing Predetermined Award Timing Predetermined [Flag] Related Party Transaction [Axis] Related Party Transaction [Axis] Asset Class [Axis] Asset Class [Axis] Entity File Number Securities Act File Number Additional paid-in-capital Additional Paid-in Capital [Member] Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Deferred financing costs Debt, Policy [Policy Text Block] Tabular List, Table Tabular List [Table Text Block] Net realized and unrealized (losses) gains (in dollars per share) Investment Company, Gain (Loss) on Investment, Per Share Investments Schedule of Investments [Text Block] Undistributed net investment income Retained Earnings, Accumulated Net Investment Income (Loss) [Member] Retained Earnings, Accumulated Net Investment Income (Loss) Schedule of Distributions Dividend Declared Dividends Declared [Table Text Block] Recent accounting standards updates New Accounting Pronouncements, Policy [Policy Text Block] Funded Capital Commitments Investment Company, Contributed Capital Investment Company, Contributed Capital Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Foreside Financial Group, LLC Foreside Financial Group, LLC [Member] Foreside Financial Group, LLC Kele Holdco, Inc. Kele Holdco, Inc. [Member] Kele Holdco, Inc. CG Group Holdings, LLC CG Group Holdings, LLC [Member] CG Group Holdings, LLC Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Per share data: Investment Company, Per Share Data [Abstract] Investment Company, Per Share Data Measurement Basis [Axis] Measurement Basis [Axis] Basic (in dollars per share) Basic earnings (loss) per share (in dollars per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] Agreements and Related Parties Related Party Transactions Disclosure [Text Block] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Proceeds from sales and paydowns of investments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales and Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales and Settlements Distributions in excess of net realized gains Retained Earnings, Accumulated Net Realized Gain (Loss) [Member] Retained Earnings, Accumulated Net Realized Gain (Loss) Discount rate Measurement Input, Discount Rate [Member] Atlas AU Bidco Pty Ltd Atlas AU Bidco Pty Ltd [Member] Atlas AU Bidco Pty Ltd Undistributed ordinary income Investment Company, Distributable Earnings (Loss), Accumulated Ordinary Income (Loss) EBITDA multiple Measurement Input, EBITDA Multiple [Member] Measurement Input Type [Domain] Measurement Input Type [Domain] Adjustment to Compensation, Amount Adjustment to Compensation Amount Concentration risk (as a percent) Concentration Risk, Percentage Payable to affiliates Affiliated Entity Affiliated Entity [Member] Net change in unrealized (depreciation) appreciation for the period relating to those Level III assets that were still held by the Company at the end of the period: Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss) MAI Capital Management Intermediate LLC MAI Capital Management Intermediate LLC [Member] MAI Capital Management Intermediate LLC Other assets Increase (Decrease) in Other Operating Assets Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Other general and administrative expenses Other General and Administrative Expense Cash and cash equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Net realized (losses) gains on investments Net realized (losses) gains on investments Net realized losses (gains) on investments Debt and Equity Securities, Realized Gain (Loss) Total net assets Net assets at the beginning of the period Net assets at the end of the period Equity, Attributable to Parent Drawn Revolving Credit Facilities Drawn Revolving Credit Facilities [Member] Drawn Revolving Credit Facilities Distributions declared to stockholders from net investment income Investment Company, Distribution, Ordinary Income Insider Trading Policies and Procedures [Line Items] Common stock, authorized (in shares) Common stock, shares authorized (in shares) Common Stock, Shares Authorized Net increase in net assets resulting from operations (in dollars per share) Investment Company, Investment Income (Loss) from Operations, Per Share Radwell Parent, LLC Radwell Parent, LLC [Member] Radwell Parent, LLC Shares issued (in shares) Stock Issued During Period, Shares, New Issues Total liabilities and net assets Liabilities and Equity Ciklum Inc. Ciklum Inc. [Member] Ciklum Inc. Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Cover [Abstract] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Net change in unrealized appreciation (depreciation) Debt and Equity Securities, Unrealized Gain (Loss) [Member] Debt and Equity Securities, Unrealized Gain (Loss) Maximum High Maximum [Member] Borrowings Long-Term Debt, Unclassified [Abstract] Accounting Policies [Abstract] New Mountain Capital New Mountain Capital [Member] New Mountain Capital Concentration Risk Type [Domain] Concentration Risk Type [Domain] PDI TA Holdings, Inc. PDI TA Holdings, Inc. [Member] PDI TA Holdings, Inc. Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Investments, At Fair Value Investments, At Fair Value [Member] Investments, At Fair Value Total expenses, net of waivers (as a percent) Investment Company, Expense Ratio Including Fee Waiver And Reimbursements Investment Company, Expense Ratio Including Fee Waiver And Reimbursements Investment, Identifier [Axis] Investment, Identifier [Axis] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Non-controlled/non-affiliated investments at fair value (cost of $1,525,141 and $1,451,005, respectively) Total investments Fair Value Investment Owned, Fair Value Interest Rate Type Risk Interest Rate Type Risk [Member] Interest Rate Type Risk Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Number of investments held Investment Company, Number Of Investments Held Investment Company, Number Of Investments Held Liabilities Liabilities [Abstract] Investment Holdings [Table] Investment Holdings [Table] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Payable for unsettled securities purchased Payable, Investment, Purchase Entity Shell Company Entity Shell Company Weighted average interest rate Long-Term Debt, Weighted Average Interest Rate, over Time Debt Securities, Floating Interest Rate Debt Securities, Floating Interest Rate [Member] Debt Securities, Floating Interest Rate Centegix Intermediate II, LLC Centegix Intermediate II, LLC [Member] Centegix Intermediate II, LLC Average debt outstanding Average debt outstanding Long-Term Debt, Average Amount Outstanding DT1 Midco Corp DT1 Midco Corp 2 [Member] DT1 Midco Corp 2 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] Statement of Stockholders' Equity [Abstract] Auctane Inc. (fka Stamps.com Inc.) Auctane Inc. (fka Stamps.com Inc.) [Member] Auctane Inc. (fka Stamps.com Inc.) Interest and dividend receivable Increase (Decrease) in Interest and Dividends Receivable RLG Holdings, LLC, First Lien RLG Holdings, LLC, First Lien [Member] RLG Holdings, LLC, First Lien Investment company, expiration of Investment period, commencement of wind up of operations, extension period Investment Company, Expiration Of Investment Period, Commencement Of Wind Up Of Operations, Extension Period Investment Company, Expiration Of Investment Period, Commencement Of Wind Up Of Operations, Extension Period Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Line of Credit Facility [Table] Line of Credit Facility [Table] Measurement Input Type [Axis] Measurement Input Type [Axis] Organizational expenses, maximum amount Organizational Expenses, Maximum, Amount Organizational Expenses, Maximum, Amount Investment, Issuer Affiliation [Axis] Investment, Issuer Affiliation [Axis] Name Measure Name Second lien Second lien Debt Securities, Second Lien [Member] Debt Securities, Second Lien DT1 Midco Corp DT1 Midco Corp [Member] DT1 Midco Corp Management fee Management Fee Expense Industry Sector [Domain] Industry Sector [Domain] Trinity Air Consultants Holdings Corporation Trinity Air Consultants Holdings Corporation [Member] Trinity Air Consultants Holdings Corporation Document Fiscal Period Focus Document Fiscal Period Focus Increase (decrease) due to reclassifications of permanent differences Investment Company, Tax Reclassification, Increase (Decrease) Financial Services & Technology Financial Services And Technology Sector [Member] Financial Services And Technology Sector Award Timing Method Award Timing Method [Text Block] Revenue multiple Measurement Input, Revenue Multiple [Member] Award Type Award Type [Axis] Businessolver.com, Inc. Businessolver.com, Inc. [Member] Businessolver.com, Inc. Net borrowings Long-Term Debt Legal Entity [Axis] Legal Entity [Axis] Total assets Assets PPV Intermediate Holdings, LLC PPV Intermediate Holdings, LLC [Member] PPV Intermediate Holdings, LLC Wells Credit Facility Wells Credit Facility [Member] Wells Credit Facility Vessco Midco Holdings, LLC Vessco Midco Holdings, LLC [Member] Vessco Midco Holdings, LLC DOCS, MSO, LLC DOCS, MSO, LLC [Member] DOCS, MSO, LLC Geographical [Domain] Geographical [Domain] OA Buyer, Inc. OA Buyer, Inc. [Member] OA Buyer, Inc. Income taxes Income Tax, Policy [Policy Text Block] Entity Address, City or Town Entity Address, City or Town LIBOR London Interbank Offered Rate L I B O R1 [Member] London Interbank Offered Rate L I B O R1 Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Ordinary dividends Investment Company, Distribution, Ordinary Income, Percentage Investment Company, Distribution, Ordinary Income, Percentage Receivable from unsettled securities sold Receivable, Investment, Sale Concentration Risk Type [Axis] Concentration Risk Type [Axis] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount GraphPAD Software, LLC GraphPAD Software, LLC [Member] GraphPAD Software, LLC Statement of Income Location, Balance [Domain] Statement of Income Location, Balance [Domain] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Distributions per share (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Principal amount Investment Owned, Balance, Principal Amount RailPros Parent, LLC RailPros Parent, LLC [Member] RailPros Parent, LLC (Increase) decrease in operating assets: Increase (Decrease) in Operating Assets [Abstract] Wells Credit Facility Broadly Syndicated Loans Wells Credit Facility Broadly Syndicated Loans [Member] Wells Credit Facility Broadly Syndicated Loans 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] Level II Fair Value, Inputs, Level 2 [Member] Oranje Holdco, Inc. Oranje Holdco, Inc. [Member] Oranje Holdco, Inc. Adjustments to reconcile net increase in net assets resulting from operations to net cash used in by 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 Deferred financing costs (net of accumulated amortization of $7,573 and $5,050, respectively) Debt Issuance Costs, Net Document Financial Statement Error Correction Document Financial Statement Error Correction [Flag] Equity method investments Equity Method Investments Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Accrued organizational and offering expenses Increase (Decrease) In Accrued Organizational And Offering Expenses Increase (Decrease) In Accrued Organizational And Offering Expenses Common stock, outstanding (in shares) Shares outstanding at end of period (in shares) Common Stock, Shares, Outstanding Capital gains Investment Company, Distribution, Long-Term Capital Gain Legends Hospitality Holding Company, LLC Legends Hospitality Holding Company, LLC [Member] Legends Hospitality Holding Company, LLC More cowbell II LLC More cowbell II LLC [Member] More cowbell II LLC PEO PEO [Member] Transfers into Level III Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Zone Climate Services, Inc. Zone Climate Services, Inc. [Member] Zone Climate Services, Inc. United States UNITED STATES 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] Vehlo Purchaser, LLC Vehlo Purchaser, LLC [Member] Vehlo Purchaser, LLC Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Beacon Pointe Harmony, LLC Beacon Pointe Harmony, LLC [Member] Beacon Pointe Harmony, LLC Cash and cash equivalents at the beginning of the period Cash and cash equivalents at the end of the period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Return of capital Investment Company, Tax Return of Capital Distribution, Percentage Investment Company, Tax Return of Capital Distribution, Percentage Wells Credit Facility, Excluding Broadly Syndicated Loans Wells Credit Facility, Excluding Broadly Syndicated Loans [Member] Wells Credit Facility, Excluding Broadly Syndicated Loans Debt instrument, basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Management and service fees, base rate calculation, assets invested, threshold Management And Service Fees, Base Rate Calculation, Assets Invested, Threshold Management And Service Fees, Base Rate Calculation, Assets Invested, Threshold Net (decrease) increase in net assets Stockholders' Equity, Period Increase (Decrease) Other assets Other Assets Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Interest payable Increase (Decrease) in Interest Payable, Net Cash paid for purchase of investments Payment for Purchase, Investment, Operating Activity Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Qualified short-term capital gains Investment Company, Distribution, Ordinary Income, Qualified Short-Term Capital Gain, Percentage Investment Company, Distribution, Ordinary Income, Qualified Short-Term Capital Gain, Percentage Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Total return (as a percent) Investment Company, Total Return Gross unrealized depreciation on investments Investment, Tax Basis, Unrealized Loss Total Investment Company, Dividend Distribution And Tax Return Of Capital Distribution Investment Company, Dividend Distribution And Tax Return Of Capital Distribution Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] MedX Holdings, LLC MedX Holdings, LLC [Member] MedX Holdings, LLC Organization, Consolidation and Presentation of Financial Statements [Abstract] Superman Holdings, LLC Superman Holdings, LLC [Member] Superman Holdings, LLC Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Title of 12(g) Security Title of 12(g) Security City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Specialty Chemicals & Materials Chemicals Sector [Member] Coupa Holdings, LLC Coupa Holdings, LLC [Member] Coupa Holdings, LLC Interest income Investment Owned, Interest Income Investment Owned, Interest Income Commitments and Contingencies Disclosure [Abstract] Proceeds from Wells Credit Facility Proceeds from Long-Term Lines of Credit Park Place Technologies, LLC Park Place Technologies, LLC [Member] Park Place Technologies, LLC Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Investment company, effect of capital transactions, per share (in dollars per share) Investment Company, Capital Share Transaction, Per Share Investment Company, Capital Share Transaction, Per Share Net cash flows provided by (used in) operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Cash received for purchase of undrawn portion of revolving credit or delayed draw facilities Proceeds from Purchase of Undrawn Portion of Investment, Operating Activity Proceeds from Purchase of Undrawn Portion of Investment, Operating Activity Related Party Transactions [Abstract] Assets under management, carrying amount Assets under Management, Carrying Amount KENG Acquisition, Inc. KENG Acquisition, Inc. [Member] KENG Acquisition, Inc. Dividends received deduction Investment Company, Distribution, Dividends Received Deduction, Percentage Investment Company, Distribution, Dividends Received Deduction, Percentage Investment company, expiration of Investment period, commencement of wind up of operations, period Investment Company, Expiration Of Investment Period, Commencement Of Wind Up Of Operations, Period Investment Company, Expiration Of Investment Period, Commencement Of Wind Up Of Operations, Period Other liabilities Other Liabilities Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] CFS Management, LLC CFS Management, LLC [Member] CFS Management, LLC PEO Total Compensation Amount PEO Total Compensation Amount Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Packaging Container and Packaging Sector [Member] Associations Finance, Inc. Associations Finance, Inc. [Member] Associations Finance, Inc. PIK Investment, Interest Rate, Paid in Kind Distribution & Logistics Distribution & Logistics [Member] Distribution & Logistics Schedule of Investments [Abstract] Equity Components [Axis] Equity Components [Axis] Legal Spend Holdings, LLC (fka Bottomline Technologies, Inc.) Legal Spend Holdings, LLC (fka Bottomline Technologies, Inc.) [Member] Legal Spend Holdings, LLC (fka Bottomline Technologies, Inc.) Entity Ex Transition Period Entity Ex Transition Period Transfers out of Level III Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 DCA Investment Holding, LLC DCA Investment Holding, LLC [Member] DCA Investment Holding, LLC CRCI Longhorn Holdings, Inc. CRCI Longhorn Holdings, Inc. [Member] CRCI Longhorn Holdings, Inc. Auditor Name Auditor Name Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Market & income approach Valuation, Market And Income Approach [Member] Valuation, Market And Income Approach Number of reportable segments Number of Reportable Segments Schedule of Financial Highlights Investment Company, Financial Highlights [Table Text Block] Meta Buyer LLC Meta Buyer LLC [Member] Meta Buyer LLC Packaging Coordinators Midco, Inc. Packaging Coordinators Midco, Inc. 2 [Member] Packaging Coordinators Midco, Inc. 2 Investment Management Agreement Assets Invested Equal to or Less than Threshold Investment Management Agreement Assets Invested Equal To Or Less Than Threshold [Member] Investment Management Agreement Assets Invested Equal To Or Less Than Threshold Supplemental disclosure of cash flow information Supplemental Cash Flow Information [Abstract] Thermostat Purchaser III, Inc. Thermostat Purchaser III, Inc. [Member] Thermostat Purchaser III, Inc. Other Performance Measure, Amount Other Performance Measure, Amount Regulation Regulatory Capital Requirements For Investment Companies [Text Block] Regulatory Capital Requirements For Investment Companies Software Software Sector [Member] Software Sector Deferred financing costs paid Payments of Debt Issuance Costs Entity Address, State or Province Entity Address, State or Province Net investment income (as a percent) Investment Company, Investment Income (Loss) Ratio Line of credit facility, borrowing capacity, first percentage Line Of Credit Facility, Borrowing Capacity, First Percentage Line Of Credit Facility, Borrowing Capacity, First Percentage Tax cost Investment, Tax Basis, Cost Fair value Fair Value Measurement, Policy [Policy Text Block] Wealth Enhancement Group, LLC Wealth Enhancement Group, LLC [Member] Wealth Enhancement Group, LLC Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Investment Type Concentration Risk Investment Type Concentration Risk [Member] Investment Type Concentration Risk KWOR Acquisition, Inc. KWOR Acquisition, Inc. [Member] KWOR Acquisition, Inc. Healthspan Buyer, LLC Healthspan Buyer, LLC [Member] Healthspan Buyer, LLC Investment Company, Net Assets [Roll Forward] Investment Company, Net Assets [Roll Forward] Individual: Individual [Axis] Distributions declared to stockholders from net investment income (in dollars per share) Investment Company, Distribution to Shareholders, Net Investment Income, Per Share Investment Company, Distribution to Shareholders, Net Investment Income, Per Share Qualified dividend income Investment Company, Distribution, Qualified Dividend Income, Percentage Investment Company, Distribution, Qualified Dividend Income, Percentage Accounting Changes and Error Corrections [Abstract] Distributions paid Payments of Ordinary Dividends, Common Stock Document Annual Report Document Annual Report Entity [Domain] Entity [Domain] Notorious Topco, LLC Notorious Topco, LLC [Member] Notorious Topco, LLC Accession Risk Management Group, Inc. Accession Risk Management Group, Inc. [Member] Accession Risk Management Group, Inc. 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] Cash interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Document Fiscal Year Focus Document Fiscal Year Focus Basis of accounting Basis of Accounting, Policy [Policy Text Block] Line of credit facility, borrowing capacity, fourth percentage Line Of Credit Facility, Borrowing Capacity, Fourth Percentage Line Of Credit Facility, Borrowing Capacity, Fourth Percentage Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Ordinary income (non-qualified) Investment Company, Distribution, Ordinary Income, Non-Qualified Investment Company, Distribution, Ordinary Income, Non-Qualified KPSKY Acquisition Inc. KPSKY Acquisition Inc. [Member] KPSKY Acquisition Inc. Distributions Investment Company, Distribution [Policy Text Block] Entity Interactive Data Current Entity Interactive Data Current Capital Commitments Investment Company, Committed Capital Principal Amount Reported Value Measurement [Member] NC Topco, LLC NC Topco, LLC [Member] NC Topco, LLC Kaseya Inc Kaseya Inc [Member] Kaseya Inc Equity [Abstract] Consumer Services Consumer Services Sector [Member] Consumer Services Sector Healthcare Healthcare Sector [Member] Bonterra LLC Bonterra LLC 2 [Member] Bonterra LLC 2 Community Management Holdings MidCo 2, LLC Community Management Holdings MidCo 2, LLC [Member] Community Management Holdings MidCo 2, LLC Segment Reporting Segment Reporting Disclosure [Text Block] Cost Cost Investment Owned, Cost Business Products Business Products Sector [Member] Business Products Sector 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] Enverus Holdings, Inc. Enverus Holdings, Inc. [Member] Enverus Holdings, Inc. Baker Tilly Advisory Group, LP Baker Tilly Advisory Group, LP [Member] Baker Tilly Advisory Group, LP Other Commitments [Line Items] Other Commitments [Line Items] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Business Services Business Services Sector [Member] Business Services Sector Weighted Average Weighted Average [Member] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Line of credit facility, borrowing capacity, second percentage Line Of Credit Facility, Borrowing Capacity, Second Percentage Line Of Credit Facility, Borrowing Capacity, Second Percentage Net assets value per share (in dollars per share) Net asset value, beginning balance (in dollars per share) Net asset value, ending balance (in dollars per share) Net Asset Value Per Share Safety Borrower Holdings LLC Safety Borrower Holdings LLC [Member] Safety Borrower Holdings LLC Entity Central Index Key Entity Central Index Key PEO Name PEO Name 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] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Pioneer Buyer I, LLC Pioneer Buyer I, LLC [Member] Pioneer Buyer I, LLC Revolving Credit Facility Revolving Credit Facility [Member] Arrangement Duration Trading Arrangement Duration Investment, Issuer Name [Domain] Investment, Issuer Name [Domain] Power Grid Holdings, Inc. Power Grid Holdings, Inc. [Member] Power Grid Holdings, Inc. Notorious Buyer, LLC Notorious Buyer, LLC [Member] Notorious Buyer, LLC Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Dividend income Dividend Income, Operating Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Foundational Education Group, Inc. Foundational Education Group, Inc. [Member] Foundational Education Group, Inc. Low Voltage Holdings Inc Low Voltage Holdings Inc [Member] Low Voltage Holdings Inc Assets Assets [Abstract] Credit Facility [Axis] Credit Facility [Axis] Other liabilities Nonrelated Party [Member] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Debt Instrument [Axis] Debt Instrument [Axis] Return of capital distributions declared to stockholders Return of capital Investment Company, Tax Return of Capital Distribution Fair Value Fair Value Disclosures [Text Block] Credit Facility [Domain] Credit Facility [Domain] TMK Hawk Parent, Corp. TMK Hawk Parent, Corp. [Member] TMK Hawk Parent, Corp. Distributions declared and payable Noncash Distribution Declared And Payable Noncash Distribution Declared And Payable Net change in unrealized (depreciation) appreciation of investments Net change in unrealized (depreciation) appreciation of investments Net change in unrealized depreciation (appreciation) of investments Debt and Equity Securities, Unrealized Gain (Loss) Net Assets Equity, Attributable to Parent [Abstract] 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] Percent of Net Assets Investment Owned, Net Assets, Percentage Entity Address, Address Line One Entity Address, Address Line One Gross unrealized appreciation on investments Investment, Tax Basis, Unrealized Gain Investments [Domain] Investments [Domain] Entity Voluntary Filers Entity Voluntary Filers Interest-related dividends Investment Company, Distribution, Ordinary Income, Interest Related, Percentage Investment Company, Distribution, Ordinary Income, Interest Related, Percentage Value of shares issued in connection with reinvestment of distributions Stock Issued GC Waves Holdings, Inc. GC Waves Holdings, Inc. [Member] GC Waves Holdings, Inc. Management and service fees, base rate Management and Service Fees, Base Rate Industry Sector [Axis] Industry Sector [Axis] Management fee payable Management Fee Payable Investment Company [Abstract] Financial Highlights Investment Company, Financial Highlights [Text Block] Fair Value as of Grant Date Award Grant Date Fair Value Entity Registrant Name Entity Registrant Name Investment Company, Financial Highlights [Line Items] Investment Company, Financial Highlights [Line Items] Schedule of Components of Accumulated Earnings (Deficit) Investment Company, Components Of Distributable Earnings (Accumulated Losses) [Table Text Block] Investment Company, Components Of Distributable Earnings (Accumulated Losses) Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Consumer Products Consumer Products Sector [Member] Consumer Products Sector Investment Management Agreement Investment Management Agreement [Member] Investment Management Agreement Schedule of Information Related to Borrowings Schedule of Long-Term Debt Instruments [Table Text Block] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Capital transactions Investment Company, Capital Share Transaction, Increase (Decrease) [Abstract] Wells Credit Facility Long-Term Debt, Fair Value Schedule of Fair Value Measurement Inputs and Valuation Techniques Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Number of operating segments Number of Operating Segments Amortization of purchase discount Accretion (Amortization) of Discounts and Premiums, Investments Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Increase (decrease) in net assets resulting from operations Net Income (Loss), Including Portion Attributable to Noncontrolling Interest [Abstract] Investment Type [Axis] Investment Type [Axis] Related and Nonrelated Parties [Axis] Related and Nonrelated Parties [Axis] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Non-cash operating activities: Non Cash Operating And Investing Activities [Abstract] Non Cash Operating And Investing Activities Repayment of Wells Credit Facility Repayments of Long-Term Lines of Credit Restatement Determination Date: Restatement Determination Date [Axis] Non-PEO NEO Non-PEO NEO [Member] Adelaide Borrower, LLC Adelaide Borrower, LLC [Member] Adelaide Borrower, LLC Management and service fees, base rate calculation based on blended rate, assets invested, maximum Management And Service Fees, Base Rate Calculation Based On Blended Rate, Assets Invested, Maximum Management And Service Fees, Base Rate Calculation Based On Blended Rate, Assets Invested, Maximum Net realized and unrealized (losses) gains Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax USRP Holdings, Inc. USRP Holdings, Inc. [Member] USRP Holdings, Inc. Interest expense Interest Expense, Debt Fee income Fee Income HIG Operations Holdings, Inc. HIG Operations Holdings, Inc. [Member] HIG Operations Holdings, Inc. Name Trading Arrangement, Individual Name Funding commitments Investment Company, Financial Support to Investee Contractually Required, Not Provided, Amount All Award Types Award Type [Domain] Runway Bidco, LLC Runway Bidco, LLC [Member] Runway Bidco, LLC Total net (decrease) increase in net assets resulting from capital transactions Investment Company, Capital Share Transaction and Dividend Distribution, Increase (Decrease) Investment Company, Capital Share Transaction and Dividend Distribution, Increase (Decrease) Equity Awards Adjustments Equity Awards Adjustments [Member] Non-cash investment income Other Noncash Income (Expense) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Compensation Amount Outstanding Recovery Compensation Amount Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Fair Value Estimate of Fair Value Measurement [Member] Unfunded Debt Securities Unfunded Debt Securities [Member] Unfunded Debt Securities Low Voltage Holdings Inc Low Voltage Holdings Inc. 2 [Member] Low Voltage Holdings Inc. 2 Schedule of Investments [Line Items] Schedule of Investments [Line Items] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Investment, Issuer Affiliation [Domain] Investment, Issuer Affiliation [Domain] Name Awards Close in Time to MNPI Disclosures, Individual Name Debt Securities, Fixed Interest Rate Debt Securities, Fixed Interest Rate [Member] Debt Securities, Fixed Interest Rate Australia AUSTRALIA Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Investment company, investment period, automatic extension Investment Company, Investment Period, Automatic Extension Investment Company, Investment Period, Automatic Extension ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Investment income Revenues [Abstract] Cash equivalents Cash Equivalents, at Carrying Value Other temporary differences Investment Company, Distributable Earnings (Loss), Accumulated Other Temporary Differences Investment Company, Distributable Earnings (Loss), Accumulated Other Temporary Differences Financial Instruments [Domain] Financial Instruments [Domain] Funded Securities Funded Securities [Member] Funded Securities Packaging Coordinators Midco, Inc. Packaging Coordinators Midco, Inc. [Member] Packaging Coordinators Midco, Inc. OEConnection LLC OEConnection LLC [Member] OEConnection LLC Auditor Firm ID Auditor Firm ID Purchases, including capitalized PIK and revolver fundings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Statement of Income Location, Balance [Axis] Statement of Income Location, Balance [Axis] Long-term capital gains Investment Company, Distribution, Long-Term Capital Gain, Percentage Investment Company, Distribution, Long-Term Capital Gain, Percentage Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Investment company, investment owned, investment objective, middle market business, EBITDA Investment Company, Investment Owned, Investment Objective, Middle Market Business, EBITDA Investment Company, Investment Owned, Investment Objective, Middle Market Business, EBITDA Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] PDQ.com Corporation PDQ.com Corporation [Member] PDQ.com Corporation Minimum Low Minimum [Member] Funded Debt Securities Funded Debt Securities [Member] Funded Debt Securities Earnings per share Earnings Per Share, Policy [Policy Text Block] Company Selected Measure Name Company Selected Measure Name Organizational expenses Organizational Expenses, Policy [Policy Text Block] Organizational Expenses, Policy Fair Value Measurement [Domain] Fair Value Measurement [Domain] Revenue recognition Revenue [Policy Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Portfolio turnover (as a percent) Investment Company, Portfolio Turnover Interest payable Interest Payable Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Proceeds from sales and paydowns of investments Proceeds from Disposition of Investment, Operating Activity Subordinated Subordinated Subordinated Debt [Member] All Executive Categories All Executive Categories [Member] First lien First lien Debt Securities, First Lien [Member] Debt Securities, First Lien NMC Crimson Holdings, Inc. NMC Crimson Holdings, Inc. [Member] NMC Crimson Holdings, Inc. Common stock, par value $0.001, 500,000,000 shares authorized, 95,740,093 and 94,236,672 shares issued and outstanding, respectively Common Stock, Value, Issued Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Infogain Corporation Infogain Corporation [Member] Infogain Corporation Diluted (in shares) Denominator for diluted weighted average share (in shares) Weighted Average Number of Shares Outstanding, Diluted Commitments and contingencies (See Note 8) Commitments and Contingencies Increase (decrease) in operating liabilities: Increase (Decrease) in Operating Liabilities [Abstract] Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Asset coverage ratio (as a percent) Investment Company, Senior Security, Indebtedness, Asset Coverage Ratio Entity Small Business Entity Small Business Income Tax Disclosure [Abstract] eResearchTechnology, Inc. eResearchTechnology, Inc. [Member] eResearchTechnology, Inc. Wells Subscription Line Wells Subscription Line [Member] Wells Subscription Line Unobservable Input Investment Company, Investment Owned, Measurement Input Daxko Acquisition Corporation Daxko Acquisition Corporation [Member] Daxko Acquisition Corporation Non-usage fee Line of Credit Facility, Commitment Fee Amount Ocala Bidco, Inc. Ocala Bidco, Inc. [Member] Ocala Bidco, Inc. Borrowings Long-Term Debt [Text Block] Document Transition Report Document Transition Report Summary of Investment Holdings [Line Items] Summary of Investment Holdings [Line Items] Victors Purchaser, LLC Victors Purchaser, LLC [Member] Victors Purchaser, LLC Schedule of Principal Amounts and Fair Values of Borrowings Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table Text Block] Recent Accounting Standards Updates Accounting Standards Update and Change in Accounting Principle [Text Block] Underlying Securities Award Underlying Securities Amount Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Distributions Income Tax Disclosure [Text Block] United Kingdom UNITED KINGDOM Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Fullsteam Operations LLC Fullsteam Operations LLC [Member] Fullsteam Operations LLC Schedule of Investments [Table] Schedule of Investments [Table] % of Capital Commitments funded Investment Company, Contributed Capital to Committed Capital Ratio Investments Including Delayed Draw Facilities Investments Including Delayed Draw Facilities [Member] Investments Including Delayed Draw Facilities Net realized losses on investments Debt and Equity Securities, Realized Gain (Loss) [Member] Debt and Equity Securities, Realized Gain (Loss) DECA Dental Holdings LLC DECA Dental Holdings LLC [Member] DECA Dental Holdings LLC Accrual for deferred financing costs Debt Issuance Costs Incurred but Not Yet Paid Debt Issuance Costs Incurred but Not Yet Paid Document Type Document Type Level III Fair Value, Inputs, Level 3 [Member] Earnings Per Share Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Allworth Financial Group, L.P. Allworth Financial Group, L.P. [Member] Allworth Financial Group, L.P. Paid in capital in excess of par Additional Paid in Capital Schedule of Costs of Investments for Tax Purposes Federal Income Tax Note [Table Text Block] PetVet Care Centers, LLC PetVet Care Centers, LLC [Member] PetVet Care Centers, LLC All Individuals All Individuals [Member] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Food & Beverage Food and Beverage Sector [Member] Name Forgone Recovery, Individual Name Dividend declared, per share amount (in dollars per share) Investment Company, Distribution to Shareholders, Per Share Statistical Measurement [Axis] Statistical Measurement [Axis] 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] Payable to affiliates Increase (Decrease) in Due to Affiliates Higginbotham Insurance Agency, Inc. Higginbotham Insurance Agency, Inc. [Member] Higginbotham Insurance Agency, Inc. Fair Value Measurement Inputs and Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Investments threshold period past due for nonaccrual status Investment Owned, Nonaccrual, Threshold Period Past Due, Investment Owned, Nonaccrual, Threshold Period Past Due, Industry Concentration Risk Industry Concentration Risk [Member] Industry Concentration Risk Line of credit facility, borrowing capacity, third percentage Line Of Credit Facility, Borrowing Capacity, Third Percentage Line Of Credit Facility, Borrowing Capacity, Third Percentage Bullhorn, Inc. Bullhorn, Inc. [Member] Bullhorn, Inc. Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Brave Parent Holdings, Inc. Brave Parent Holdings, Inc. [Member] Brave Parent Holdings, Inc. The Ultimus Group Midco, LLC The Ultimus Group Midco, LLC [Member] The Ultimus Group Midco, LLC Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Weighted average shares of common stock outstanding Weighted Average Shares Of Common Stock Outstanding [Abstract] Weighted Average Shares Of Common Stock Outstanding Geographical [Axis] Geographical [Axis] CCBlue Bidco, Inc. CCBlue Bidco, Inc. [Member] CCBlue Bidco, Inc. Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Other Other Valuation Technique [Member] Other Valuation Technique Level I Fair Value, Inputs, Level 1 [Member] Wells Credit Facility Line of credit Long-Term Line of Credit 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] Related Party Transaction [Table] Related Party Transaction [Table] Diluted (in dollars per share) Diluted earnings (loss) per share (in dollars per share) Earnings Per Share, Diluted Investment Management Agreement Assets Invested Greater than Threshold Investment Management Agreement Assets Invested Greater Than Threshold [Member] Investment Management Agreement Assets Invested Greater Than Threshold Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Reinvestment of distributions Stock Issued During Period, Value, Dividend Reinvestment Plan Earnings per share Earnings Per Share [Abstract] Net investment income Net investment income Investment Income, Operating, after Expense and Tax Auditor Location Auditor Location AAH Topco, LLC AAH Topco, LLC [Member] AAH Topco, LLC ACI Group Holdings, Inc. ACI Group Holdings, Inc. [Member] ACI Group Holdings, Inc. Audit Information [Abstract] Audit Information [Abstract] Schedule of Tax Character of Distributions Investment Company, Distribution To Shareholders [Table Text Block] Investment Company, Distribution To Shareholders Interest income (excluding Payment-in-kind ("PIK") interest income) Interest Income, Operating, Paid in Cash Investment company, investment period, automatic extension or termination, written notice period, minimum Investment Company, Investment Period, Automatic Extension Or Termination, Written Notice Period, Minimum Investment Company, Investment Period, Automatic Extension Or Termination, Written Notice Period, Minimum GS Acquisitionco, Inc. GS Acquisitionco, Inc. [Member] GS Acquisitionco, Inc. Administrative expenses Administrative Fees Expense Investment Company, Financial Highlights [Table] Investment Company, Financial Highlights [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Total investments at fair value Tax Basis Of Investments, Fair Value For Income Tax Purposes Tax Basis Of Investments, Fair Value For Income Tax Purposes Bonterra LLC Bonterra LLC [Member] Bonterra LLC Award Timing Disclosures [Line Items] Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Spread Investment, Basis Spread, Variable Rate Net Assets Equity [Text Block] YLG Holdings, Inc. YLG Holdings, Inc. [Member] YLG Holdings, Inc. Education Education Sector [Member] Education Sector Effective interest rate Debt Instrument, Interest Rate During Period Principal amount, shares (in shares) Investment Owned, Balance, Shares Net increase in net assets resulting from operations Net increase in net assets resulting from operations Numerator for basic & diluted earnings per share: Net Income (Loss) Attributable to Parent Expiration Date Trading Arrangement Expiration Date Net investment income (in dollars per share) Investment Company, Investment Income (Loss), Per Share, Basic Other liabilities Increase (Decrease) in Other Operating Liabilities Receivable from unsettled securities sold Increase (Decrease) in Receivables under Repurchase Agreements PIK interest income Interest Income, Operating, Paid in Kind Total Investments [Member] Next Holdco, LLC Next Holdco, LLC [Member] Next Holdco, LLC Adoption Date Trading Arrangement Adoption Date Ordinary income (qualified) Investment Company, Distribution, Ordinary Income, Qualified Investment Company, Distribution, Ordinary Income, Qualified Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Diamondback Acquisition, Inc. Diamondback Acquisition, Inc. [Member] Diamondback Acquisition, Inc. Jersey JERSEY Entity Current Reporting Status Entity Current Reporting Status Schedule of Investments Investment Holdings, Schedule of Investments [Table Text Block] Total coupon/Interest rate Investment Interest Rate Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Al Altius US Bidco, Inc. Al Altius US Bidco, Inc. [Member] Al Altius US Bidco, Inc. Non-cash financing activities: Noncash Financing Items [Abstract] Noncash Financing Items Line of Credit Line of Credit [Member] Accumulated (overdistributed) undistributed earnings Total Retained Earnings (Accumulated Deficit) Return of capital distributions declared to stockholders (in dollars per share) Investment Company, Tax Return of Capital Distribution, Per Share Total expenses, before waivers (as a percent) Investment Company, Expense Ratio Before Fee Waiver And Reimbursements Investment Company, Expense Ratio Before Fee Waiver And Reimbursements Financial Instrument [Axis] Financial Instrument [Axis] Statement of Financial Position [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Executive Category: Executive Category [Axis] Wrench Group LLC Wrench Group LLC [Member] Wrench Group LLC Interest and other financing expenses Interest Expense, Operating and Nonoperating Current Fiscal Year End Date Current Fiscal Year End Date 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] Specialtycare, Inc. Specialtycare, Inc. [Member] Specialtycare, Inc. Professional fees Professional Fees Statement [Table] Statement [Table] KENE Acquisition, Inc. KENE Acquisition, Inc. [Member] KENE Acquisition, Inc. Cash flows from financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Cronos Crimson Holdings, Inc. (f/k/a NMC Crimson Holdings, Inc.) Cronos Crimson Holdings, Inc. (f/k/a NMC Crimson Holdings, Inc.) [Member] Cronos Crimson Holdings, Inc. (f/k/a NMC Crimson Holdings, Inc.) Investments Excluding Drawn Revolvers Investments Excluding Drawn Revolvers [Member] Investments Excluding Drawn Revolvers MRI Software LLC MRI Software LLC [Member] MRI Software LLC RXB Holdings, Inc. RXB Holdings, Inc. [Member] RXB Holdings, Inc. FS WhiteWater Borrower, LLC FS WhiteWater Borrower, LLC [Member] FS WhiteWater Borrower, LLC Variable Rate [Domain] Variable Rate [Domain] Formation and Business Purpose Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Schedule of Changes in Level III Portfolio Investments Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Management fee payable Increase (Decrease) in Management Fee Payable All Adjustments to Compensation All Adjustments to Compensation [Member] Amendment Flag Amendment Flag Distributions declared to stockholders from realized gains Investment Company, Distribution, Capital Gain Investment Company, Distribution, Capital Gain Other Commitments [Table] Other Commitments [Table] Termination Date Trading Arrangement Termination Date Net cash flows (used in) provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Lighthouse Buyer, Inc. Lighthouse Buyer, Inc. [Member] Lighthouse Buyer, Inc. Schedule of Portfolio Investments by Level in the Fair Value Hierarchy Fair Value, Assets Measured on Recurring Basis [Table Text Block] Basic (in shares) Denominator for basic weighted average share (in shares) Average weighted shares outstanding for the period (in shares) Weighted Average Number of Shares Outstanding, Basic Investment Company, Financial Highlights [Roll Forward] Investment Company, Financial Highlights [Roll Forward] Interest and dividend receivable Dividend and Interest Receivable Schedule of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Investment, Issuer Name [Axis] Investment, Issuer Name [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Subsequent Events [Abstract] Segment Reporting [Abstract] CB Buyer, Inc. CB Buyer, Inc. [Member] CB Buyer, Inc. Schedule of Investment Company, Change in Net Assets Investment Company, Change in Net Assets [Table Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Distributions declared to stockholders from realized gains (in dollars per share) Investment Company, Distribution to Shareholders, Realized Gains, Per Share Investment Company, Distribution to Shareholders, Realized Gains, Per Share Debt Disclosure [Abstract] Tennessee Bidco Limited Tennessee Bidco Limited [Member] Tennessee Bidco Limited Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Fortis Solutions Group, LLC Fortis Solutions Group, LLC [Member] Fortis Solutions Group, LLC Amortization of deferred financing costs Amortization of financing costs Amortization of Debt Issuance Costs TigerConnect, Inc. TigerConnect, Inc. [Member] TigerConnect, Inc. Total expenses Investment Income, Investment Expense Entity Tax Identification Number Entity Tax Identification Number Galway Borrower LLC Galway Borrower LLC [Member] Galway Borrower LLC 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] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Model N, Inc. Model N, Inc. [Member] Model N, Inc. Common stock, par value (in dollars per share) Common stock, par or stated value per share (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, issued (in shares) Common Stock, Shares, Issued Use of estimates Use of Estimates, Policy [Policy Text Block] Accumulated capital gains (capital loss carryforwards) Investment Company, Distributable Earnings (Loss), Accumulated Long-Term Capital Gain (Accumulated Capital Loss Carryforward) Investment Company, Distributable Earnings (Loss), Accumulated Long-Term Capital Gain (Accumulated Capital Loss Carryforward) Non-cash activity on investments Noncash Investment Activities, Operating Noncash Investment Activities, Operating Entity Public Float Entity Public Float Payable for unsettled securities purchased Increase (Decrease) in Payables under Repurchase Agreements Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount KWOR Intermediate I, LLC KWOR Intermediate I, LLC 2 [Member] KWOR Intermediate I, LLC 2 CoreTrust Purchasing Group LLC CoreTrust Purchasing Group LLC [Member] CoreTrust Purchasing Group LLC Associations, Inc. Associations, Inc. [Member] Associations, Inc. Subsequent Events Subsequent Events [Text Block] Insider Trading Arrangements [Line Items] Unrealized appreciation (depreciation) Investment Company, Distributable Earnings (Loss), Accumulated Appreciation (Depreciation) Average net assets for the period Average Net Assets Average Net Assets Equity Securities Equity Securities [Member] Calabrio, Inc. Calabrio, Inc. [Member] Calabrio, Inc. Deferred financing costs, accumulated amortization Accumulated Amortization, Debt Issuance Costs Syndigo LLC Syndigo LLC [Member] Syndigo LLC iCIMS, Inc. iCIMS, Inc. [Member] iCIMS, Inc. Incurred excise taxes Excise Taxes Collected Total liabilities Liabilities Drawn Revolvers Drawn Revolvers [Member] Drawn Revolvers Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Shares issued from the reinvestment of distribution (in shares) Stock issued during period, shares, dividend reinvestment plan (in shares) Stock Issued During Period, Shares, Dividend Reinvestment Plan Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Interest and other financing expenses Interest Expense, Policy [Policy Text Block] Expenses Operating Expenses [Abstract] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Asset Class [Domain] Asset Class [Domain] Ratio to average net assets: Investment Company, Ratio To Average Net Assets [Abstract] Investment Company, Ratio To Average Net Assets Total gains or losses included in earnings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Equity and other Other Security Investments [Member] Statement [Line Items] Statement [Line Items] Variable Rate [Axis] Variable Rate [Axis] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and cash equivalents Cash and Cash Equivalent Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Percentage of total assets at fair value considered non-qualifying (as a percent) Investment Owned, At Fair Value, Non-Qualifying Assets, Percent Of Total Assets Investment Owned, At Fair Value, Non-Qualifying Assets, Percent Of Total Assets Total investment income Gross Investment Income, Operating Net increase in shares of common stock outstanding (in shares) Stock Issued During Period, Shares, Period Increase (Decrease) Diligent Corporation Diligent Corporation [Member] Diligent Corporation Capital share activity Investment Company, Capital Share Transactions, Stock Issued [Abstract] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation