| CONSOLIDATED SCHEDULE OF INVESTMENTS (Parentheticals) - USD ($)
 | Sep. 30, 2023 | Sep. 30, 2022 | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 172.50% | [1],[2],[3],[4],[5] | 205.90% | [6],[7],[8],[9],[10] | 
| Investments, at fair value |  | $ 704,815,000 | [4] | $ 649,615,000 | [9] | 
| Percentage threshold of qualified assets representing total assets in order to acquire non-qualified assets |  | 70.00% |  | 70.00% |  | 
| Percentage of acquired non-qualifying assets of total assets |  | 0.10% |  |  |  | 
| Debt instrument, leverage maturity, terms |  | 2 years |  | 2 years |  | 
| Cumulative gross unrealized depreciation |  | $ 56,900,000 |  | $ 35,200,000 |  | 
| Cumulative net unrealized appreciation |  | 33,700,000 |  | 52,300,000 |  | 
| Cumulative gross unrealized appreciation (depreciation) for federal income tax purposes |  | (23,200,000) |  | 17,100,000 |  | 
| Based on a tax cost |  | $ 728,000,000 |  | 666,700,000 |  | 
| Funko Acquisition Holdings, LLC |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  |  |  | $ 22,000 |  | 
| Percentage of acquired non-qualifying assets of total assets |  |  |  | 1.00% |  | 
| Secured Overnight Financing Rate (SOFR) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  | 5.32% |  | 3.04% |  | 
| Secured Overnight Financing Rate (SOFR) _90 day |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  | 5.40% |  |  |  | 
| LIBOR |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  |  |  | 6.50% |  | 
| Investment, basis spread, variable rate, floor |  |  |  | 1.00% |  | 
| London Interbank Offered Rate (LIBOR)_30 day |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  |  |  | 3.14% |  | 
| London Interbank Offered Rate (LIBOR)_90 day |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  |  |  | 3.75% |  | 
| Prime Rate |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  |  |  | 6.25% |  | 
| Collateral Pledged |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 628,300,000 |  | $ 577,600,000 |  | 
| Investment, Identifier [Axis]: Leeds Novamark Capital I, L.P. – Limited Partnership Interest |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Line of credit facility, available | [6],[7],[8],[10],[11],[12],[13] |  |  | 843,000 |  | 
| Investments, at fair value | [11],[12],[13] |  |  | 6,397,000 |  | 
| Investment, Identifier [Axis]: Antenna Research Associates, Inc. – Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | 13,734,000 |  | 
| Investment, Identifier [Axis]: Engineering Manufacturing Technologies, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | 1,773,000 |  | 
| Investment, Identifier [Axis]: Ohio Armor Holdings, LLC – Common Equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | $ 1,017,000 |  | 
| Investment, Identifier [Axis]: 8th Avenue Food & Provisions, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.90% | [1],[2],[3],[5],[15] | 7.80% | [6],[7],[8],[10],[16] | 
| Investment, interest rate, paid in cash |  | 13.20% | [1],[2],[3],[5],[15] | 10.90% | [6],[7],[8],[10],[16] | 
| Investments, at fair value |  | $ 2,495,000 | [15] | $ 3,020,000 | [16] | 
| Investment, Identifier [Axis]: ALS Education, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.00% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.30% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 3,000,000 | [1],[2],[3],[5],[17] | $ 3,000,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 0 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: ALS Education, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.00% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.30% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 18,700,000 | [17] | $ 19,468,000 | [18] | 
| Investment, Identifier [Axis]: Antenna Research Associates, Inc. – Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 18,436,000 |  |  |  | 
| Investment, Identifier [Axis]: Antenna Research Associates, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 10.00% | [1],[2],[3],[5],[19] | 10.00% | [6],[7],[8],[10],[14] | 
| Investment, interest rate, paid in cash |  | 15.30% | [1],[2],[3],[5],[19] | 13.00% | [6],[7],[8],[10],[14] | 
| Investment, interest rate, paid in kind |  | 4.00% | [1],[2],[3],[5],[19] | 4.00% | [6],[7],[8],[10],[14] | 
| Investments, at fair value |  | $ 30,048,000 | [19] | $ 21,973,000 | [14] | 
| Investment, Identifier [Axis]: Arc Drilling Holdings LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 403,000 | [19],[20] | $ 0 | [12],[14] | 
| Investment, Identifier [Axis]: Arc Drilling Holdings LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 11.50% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 10.50% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17] | 6.30% |  |  |  | 
| Line of credit facility, available |  | $ 1,000,000 | [1],[2],[3],[5],[17] | $ 1,000,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 0 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: Arc Drilling Holdings LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 11.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 10.50% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17] | 6.30% |  |  |  | 
| Investments, at fair value | [17] | $ 5,724,000 |  |  |  | 
| Investment, Identifier [Axis]: Arc Drilling Holdings LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 9.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 12.60% |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18] |  |  | 3.00% |  | 
| Investments, at fair value | [18] |  |  | $ 5,350,000 |  | 
| Investment, Identifier [Axis]: Axios Industrial Group, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.60% | [1],[2],[3],[5],[17] | 9.50% | [6],[7],[8],[10],[18],[21] | 
| Investment, interest rate, paid in cash |  | 13.90% | [1],[2],[3],[5],[17] | 12.60% | [6],[7],[8],[10],[18],[21] | 
| Investments, at fair value |  | $ 11,291,000 | [17] | $ 8,741,000 | [18],[21] | 
| Investment, Identifier [Axis]: Axios Industrial Group, LLC– Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[21] |  |  | 9.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[21] |  |  | 12.60% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18],[21] |  |  | $ 5,000,000 |  | 
| Investments, at fair value | [18],[21] |  |  | 2,914,000 |  | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc. – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17],[22] | 2.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[22] | 7.30% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17],[22] | $ 0 |  |  |  | 
| Investments, at fair value | [17],[22] | $ 978,000 |  |  |  | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17],[22] | 2.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[22] | 7.30% |  |  |  | 
| Investments, at fair value | [17],[22] | $ 4,890,000 |  |  |  | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc.(S) – Common Stock Warrant |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 | [19],[20],[22] | $ 25,000 | [12],[14],[23] | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc.(S) – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[23] |  |  | 11.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[23] |  |  | 14.10% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18],[23] |  |  | $ 0 |  | 
| Investments, at fair value | [18],[23] |  |  | 1,146,000 |  | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc.(S) – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 | [19],[20],[22] | $ 2,718,000 | [12],[14],[23] | 
| Investment, Identifier [Axis]: B+T Group Acquisition, Inc.(S) – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[23] |  |  | 11.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[23] |  |  | 14.10% |  | 
| Investments, at fair value | [18],[23] |  |  | $ 5,730,000 |  | 
| Investment, Identifier [Axis]: CHA Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[15],[24] | 9.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[15],[24] | 14.40% |  |  |  | 
| Investments, at fair value | [15],[24] | $ 2,820,000 |  |  |  | 
| Investment, Identifier [Axis]: CHA Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[16],[25] |  |  | 8.80% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[16],[25] |  |  | 12.50% |  | 
| Investments, at fair value | [16],[25] |  |  | $ 2,700,000 |  | 
| Investment, Identifier [Axis]: CPM Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[16] |  |  | 8.30% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[16] |  |  | 11.40% |  | 
| Investments, at fair value | [16] |  |  | $ 758,000 |  | 
| Investment, Identifier [Axis]: Cafe Zupas – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 6.80% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.10% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 1,500,000 |  |  |  | 
| Investments, at fair value | [17] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: Café Zupas – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 6.80% | [1],[2],[3],[5],[17] | 7.40% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.10% | [1],[2],[3],[5],[17] | 10.50% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 2,070,000 | [1],[2],[3],[5],[17] | $ 0 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 7,850,000 | [17] | $ 1,958,000 | [18] | 
| Investment, Identifier [Axis]: Café Zupas – Line of Credit, |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.40% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.50% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18] |  |  | $ 4,000,000 |  | 
| Investments, at fair value | [18] |  |  | $ 0 |  | 
| Investment, Identifier [Axis]: Café Zupas – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 6.80% | [1],[2],[3],[5],[17] | 7.40% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.10% | [1],[2],[3],[5],[17] | 10.50% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 23,108,000 | [17] | $ 23,313,000 | [18] | 
| Investment, Identifier [Axis]: Canopy Safety Brands, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 2,404,000 | [19],[20] | 647,000 | [12],[14] | 
| Investment, Identifier [Axis]: Canopy Safety Brands, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 857,000 | [19],[20] | 798,000 | [12],[14] | 
| Investment, Identifier [Axis]: Canopy Safety Brands, LLC—Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 2,404,000 |  | 647,000 |  | 
| Investment, Identifier [Axis]: Canopy Safety Brands, LLC—Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 857,000 |  | $ 798,000 |  | 
| Investment, Identifier [Axis]: Chinese Yellow Pages Company – Line of Credit, |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[14],[26],[27] |  |  | 4.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14],[26],[27] |  |  | 10.30% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[14],[26],[27] |  |  | $ 0 |  | 
| Investments, at fair value | [14],[26],[27] |  |  | 0 |  | 
| Investment, Identifier [Axis]: Circuitronics EMS Holdings LLC – Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | 0 |  | 
| Investment, Identifier [Axis]: Circuitronics EMS Holdings LLC—Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 |  | $ 0 |  | 
| Investment, Identifier [Axis]: DKI Ventures, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[28] | 9.00% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17],[28] | $ 170,000 |  |  |  | 
| Investments, at fair value | [17],[28] | $ 113,000 |  |  |  | 
| Investment, Identifier [Axis]: DKI Ventures, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 8.00% |  | 
| Investment, interest rate, paid in cash |  | 9.00% | [1],[2],[3],[5],[17],[28] | 11.00% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 3,253,000 | [17],[28] | $ 4,554,000 | [18] | 
| Investment, Identifier [Axis]: Defiance Integrated Technologies, Inc. – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 3,948,000 | [19],[20] | $ 1,147,000 | [12],[14] | 
| Investment, Identifier [Axis]: Defiance Integrated Technologies, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[19] | 9.60% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[19] | 14.90% |  |  |  | 
| Investments, at fair value | [19] | $ 7,425,000 |  |  |  | 
| Investment, Identifier [Axis]: Defiance Integrated Technologies, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[14] |  |  | 9.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14] |  |  | 12.60% |  | 
| Investments, at fair value | [14] |  |  | $ 7,665,000 |  | 
| Investment, Identifier [Axis]: Defiance Integrated Technologies, Inc.—Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 3,948,000 |  | 1,147,000 |  | 
| Investment, Identifier [Axis]: Defiance Integrated Technologies, Inc.—Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 7,425,000 |  | $ 7,665,000 |  | 
| Investment, Identifier [Axis]: ENET Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.30% | [1],[2],[3],[5],[17] | 7.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.60% | [1],[2],[3],[5],[17] | 10.40% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 21,397,000 | [17] | $ 23,142,000 | [18] | 
| Investment, Identifier [Axis]: Edge Adhesives Holdings, Inc. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 | [19],[20],[22] | $ 0 | [12],[14],[23] | 
| Investment, Identifier [Axis]: Edge Adhesives Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[19],[22],[29] | 5.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[19],[22],[29] | 10.80% |  |  |  | 
| Investments, at fair value | [19],[22],[29] | $ 2,895,000 |  |  |  | 
| Investment, Identifier [Axis]: Edge Adhesives Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[14],[23] |  |  | 5.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14],[23] |  |  | 8.60% |  | 
| Investments, at fair value | [14],[23] |  |  | $ 2,550,000 |  | 
| Investment, Identifier [Axis]: Edge Adhesives Holdings, Inc.—Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 0 |  | 
| Investment, Identifier [Axis]: Edge Adhesives Holdings, Inc.—Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 2,895,000 |  | $ 2,550,000 |  | 
| Investment, Identifier [Axis]: Eegee’s LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.80% | [1],[2],[3],[5],[17] | 8.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.10% | [1],[2],[3],[5],[17] | 11.40% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 4,500,000 | [1],[2],[3],[5],[17] | $ 4,500,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 2,865,000 | [17] | $ 2,910,000 | [18] | 
| Investment, Identifier [Axis]: Eegee’s LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.80% | [1],[2],[3],[5],[17] | 8.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.10% | [1],[2],[3],[5],[17] | 11.40% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 1,000,000 | [1],[2],[3],[5],[17] | $ 1,000,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 0 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: Eegee’s LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.80% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 13.10% |  |  |  | 
| Investments, at fair value | [17] | $ 16,235,000 |  |  |  | 
| Investment, Identifier [Axis]: Eegee’s LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 8.30% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 11.40% |  | 
| Investments, at fair value | [18] |  |  | $ 16,490,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.10% |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18] |  |  | 1.50% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18] |  |  | $ 0 |  | 
| Investments, at fair value | [18] |  |  | $ 4,885,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 8.30% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 11.40% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18] |  |  | $ 3,000,000 |  | 
| Investments, at fair value | [18] |  |  | 0 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 4,265,000 | [19],[20] | $ 2,842,000 | [12],[14],[23] | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.10% |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18] |  |  | 1.50% |  | 
| Investments, at fair value | [18] |  |  | $ 22,962,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.10% |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18] |  |  | 2.50% |  | 
| Investments, at fair value | [18] |  |  | $ 4,407,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC—Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 4,885,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC—Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 0 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC—Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 4,265,000 |  | 2,842,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC—Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 22,962,000 |  | 
| Investment, Identifier [Axis]: Encore Dredging Holdings, LLC—Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | $ 4,407,000 |  | 
| Investment, Identifier [Axis]: Engineering Manufacturing Technologies, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: Engineering Manufacturing Technologies, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.30% | [1],[2],[3],[5],[17] | 8.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.60% | [1],[2],[3],[5],[17] | 11.40% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 3,000,000 | [1],[2],[3],[5],[17] | $ 3,000,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 0 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: Engineering Manufacturing Technologies, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.30% | [1],[2],[3],[5],[17] | 8.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.60% | [1],[2],[3],[5],[17] | 11.40% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 19,726,000 | [17] | $ 22,134,000 | [18] | 
| Investment, Identifier [Axis]: FES Resources Holdings LLC – Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 | [19],[20] | 0 | [12],[14] | 
| Investment, Identifier [Axis]: FES Resources Holdings LLC – Preferred Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 4,508,000 | [19],[20] | $ 0 | [12],[14] | 
| Investment, Identifier [Axis]: Fix-It Group, LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.10% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18],[25] | 
| Line of credit facility, available |  | $ 0 | [1],[2],[3],[5],[17] | $ 10,000,000 | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 6,894,000 | [17] | $ 0 | [18],[25] | 
| Investment, Identifier [Axis]: Fix-It Group, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.10% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18],[25] | 
| Line of credit facility, available |  | $ 2,500,000 | [1],[2],[3],[5],[17] | $ 3,000,000 | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 499,000 | [17] | $ 0 | [18],[25] | 
| Investment, Identifier [Axis]: Fix-It Group, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.10% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 12,170,000 | [17] | $ 9,950,000 | [18],[25] | 
| Investment, Identifier [Axis]: Frontier Financial Group Inc. – Convertible Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[14],[30] |  |  | 6.00% |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[19],[28] | 6.00% |  |  |  | 
| Investments, at fair value |  | $ 24,000 | [19],[28] | $ 55,000 | [14],[30] | 
| Investment, Identifier [Axis]: Frontier Financial Group Inc. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 | [19],[20] | 0 | [12],[14] | 
| Investment, Identifier [Axis]: Frontier Financial Group Inc. – Preferred Stock Warrant |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 | [19],[20] | 0 | [12],[14] | 
| Investment, Identifier [Axis]: Funko Acquisition Holdings, LLC(S) – Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 22,000 | [20],[22],[31] | 58,000 | [12],[23],[32] | 
| Investment, Identifier [Axis]: GFRC 360, LLC – Common Stock Warrants |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 | [19],[20] | $ 0 | [12],[14] | 
| Investment, Identifier [Axis]: GFRC 360, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.30% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 175,000 | [1],[2],[3],[5],[17] | $ 500,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | 1,205,000 | [17] | 681,000 | [18] | 
| Investment, Identifier [Axis]: GFRC 360, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 253,000 | [19],[20] | $ 551,000 | [12],[14] | 
| Investment, Identifier [Axis]: GFRC 360, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.30% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 945,000 | [17] | $ 973,000 | [18] | 
| Investment, Identifier [Axis]: GSM MidCo LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 1,562,000 | [19],[20] | $ 1,359,000 | [12],[14] | 
| Investment, Identifier [Axis]: Giving Home Health Care, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  | 12.50% | [1],[2],[3],[5],[17],[28] | 12.50% | [6],[7],[8],[10],[18],[30] | 
| Investments, at fair value |  | $ 28,800,000 | [17],[28] | $ 28,800,000 | [18],[30] | 
| Investment, Identifier [Axis]: Giving Home Health Care, LLC – Warrant |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 2,794,000 | [19],[20] | $ 19,000 | [12],[14] | 
| Investment, Identifier [Axis]: Gray Matter Systems, LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[30] |  |  | 11.30% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18],[30] |  |  | $ 4,000,000 |  | 
| Investments, at fair value | [18],[30] |  |  | $ 2,481,000 |  | 
| Investment, Identifier [Axis]: Gray Matter Systems, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash |  | 12.00% | [1],[2],[3],[5],[17],[28] | 11.30% | [6],[7],[8],[10],[18],[30] | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17],[28] | 2.00% |  |  |  | 
| Investments, at fair value |  | $ 13,645,000 | [17],[28] | $ 2,084,000 | [18],[30] | 
| Investment, Identifier [Axis]: HH-Inspire Acquisition, Inc. – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[25] |  |  | 6.80% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[25] |  |  | 9.90% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18],[25] |  |  | $ 0 |  | 
| Investments, at fair value | [18],[25] |  |  | $ 9,925,000 |  | 
| Investment, Identifier [Axis]: HH-Inspire Acquisition, Inc. – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17],[24] | 6.80% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17],[24] | 9.90% | [6],[7],[8],[10],[18],[25] | 
| Line of credit facility, available |  | $ 478,000 | [1],[2],[3],[5],[17],[24] | $ 1,500,000 | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | 1,347,000 | [17],[24] | 1,489,000 | [18],[25] | 
| Investment, Identifier [Axis]: HH-Inspire Acquisition, Inc. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 3,451,000 | [19],[20] | $ 945,000 | [12],[14] | 
| Investment, Identifier [Axis]: HH-Inspire Acquisition, Inc. – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17],[24] | 6.80% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17],[24] | 9.90% | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 15,872,000 | [17],[24] | $ 15,880,000 | [18],[25] | 
| Investment, Identifier [Axis]: HH-Inspire Acquisition, Inc. – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17],[24] | 6.80% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 13.40% | [1],[2],[3],[5],[17],[24] | 9.90% | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 3,197,000 | [17],[24] | $ 7,940,000 | [18],[25] | 
| Investment, Identifier [Axis]: Imperative Holdings Corporation – Preferred Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 2,318,000 | [19],[20] | $ 2,028,000 | [12],[14] | 
| Investment, Identifier [Axis]: Imperative Holdings Corporation – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 9.80% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 15.10% |  |  |  | 
| Investments, at fair value | [17] | $ 20,858,000 |  |  |  | 
| Investment, Identifier [Axis]: Imperative Holdings Corporation – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 10.30% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 13.40% |  | 
| Investments, at fair value | [18] |  |  | $ 23,295,000 |  | 
| Investment, Identifier [Axis]: LWO Acquisitions Company LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [14],[33] |  |  | 0 |  | 
| Investment, Identifier [Axis]: LWO Acquisitions Company LLC—Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 |  | 0 |  | 
| Investment, Identifier [Axis]: Leadpoint Business Services, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 8.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 13.80% |  |  |  | 
| Investments, at fair value | [17] | $ 13,399,000 |  |  |  | 
| Investment, Identifier [Axis]: Leeds Novamark Capital I, L.P. – Limited Partnership Interest |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[20],[34],[35] | 843,000 |  |  |  | 
| Investments, at fair value | [20],[34],[35] | $ 231,000 |  |  |  | 
| Investment, Identifier [Axis]: Lonestar EMS, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[19],[28] | 8.00% |  |  |  | 
| Investments, at fair value | [19],[28] | $ 3,927,000 |  |  |  | 
| Investment, Identifier [Axis]: Lonestar EMS, LLC - Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 0 |  | 
| Investment, Identifier [Axis]: Lonestar EMS, LLC – Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 | [19],[20] | $ 0 | [12],[14] | 
| Investment, Identifier [Axis]: Lonestar EMS, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14],[30] |  |  | 8.00% |  | 
| Investments, at fair value | [14],[30] |  |  | $ 3,030,000 |  | 
| Investment, Identifier [Axis]: Lonestar EMS, LLC—Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 3,927,000 |  | $ 3,030,000 |  | 
| Investment, Identifier [Axis]: MCG Energy Solutions, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.60% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18] |  |  | $ 3,000,000 |  | 
| Investments, at fair value | [18] |  |  | 0 |  | 
| Investment, Identifier [Axis]: MCG Energy Solutions, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 8,904,000 | [19],[20] | $ 8,151,000 | [14] | 
| Investment, Identifier [Axis]: MCG Energy Solutions, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.60% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.90% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17] | 3.50% |  |  |  | 
| Investments, at fair value | [17] | $ 17,628,000 |  |  |  | 
| Investment, Identifier [Axis]: MCG Energy Solutions, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.60% |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18] |  |  | 3.50% |  | 
| Investments, at fair value | [18] |  |  | $ 19,779,000 |  | 
| Investment, Identifier [Axis]: NeoGraf Solutions LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: NeoGraf Solutions LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 11.00% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17] | 1.30% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 4,500,000 |  |  |  | 
| Investments, at fair value | [17] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: NeoGraf Solutions LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 11.00% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17] | 1.30% |  |  |  | 
| Investments, at fair value | [17] | $ 26,000,000 |  |  |  | 
| Investment, Identifier [Axis]: NetFortris Corp. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | $ 469,000 |  | 
| Investment, Identifier [Axis]: OCI, LLC – Common Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: OCI, LLC – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.80% |  |  |  | 
| Investments, at fair value | [17] | $ 19,800,000 |  |  |  | 
| Investment, Identifier [Axis]: OCI, LLC – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[28] | 7.00% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17],[28] | 7.00% |  |  |  | 
| Investments, at fair value | [17],[28] | $ 1,992,000 |  |  |  | 
| Investment, Identifier [Axis]: Ohio Armor Holdings, LLC – Common Equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 680,000 |  |  |  | 
| Investment, Identifier [Axis]: Ohio Armor Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 8.00% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 13.30% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 17,294,000 | [17] | $ 18,558,000 | [18] | 
| Investment, Identifier [Axis]: PIC 360, LLC – Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 284,000 | [19],[20] | 3,454,000 | [12],[14] | 
| Investment, Identifier [Axis]: PIC 360, LLC—Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 284,000 |  | $ 3,454,000 |  | 
| Investment, Identifier [Axis]: Pansophic Learning, Ltd. – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.50% | [1],[2],[3],[5],[17],[24] | 7.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.90% | [1],[2],[3],[5],[17],[24] | 10.40% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 27,965,000 | [17],[24] | $ 27,825,000 | [18] | 
| Investment, Identifier [Axis]: Pansophic Learning, Ltd. – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.50% | [1],[2],[3],[5],[17],[24] | 7.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.90% | [1],[2],[3],[5],[17],[24] | 10.40% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 4,994,000 | [17],[24] | $ 4,969,000 | [18] | 
| Investment, Identifier [Axis]: R2i Holdings, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[30],[36] |  |  | 8.00% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[30],[36] |  |  | $ 1,171,000 |  | 
| Investments, at fair value | [30],[36] |  |  | $ 829,000 |  | 
| Investment, Identifier [Axis]: R2i Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[30],[36] |  |  | 8.00% |  | 
| Investments, at fair value | [30],[36] |  |  | $ 18,000,000 |  | 
| Investment, Identifier [Axis]: Salt & Straw, LLC – Common Warrant |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 31,000 |  |  |  | 
| Investment, Identifier [Axis]: Salt & Straw, LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 9.10% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 14.40% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 1,300,000 | [1],[2],[3],[5],[17] | $ 11,500,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 9,715,000 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: Salt & Straw, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 9.10% | [1],[2],[3],[5],[17] | 8.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 14.40% | [1],[2],[3],[5],[17] | 11.10% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 2,000,000 | [1],[2],[3],[5],[17] | $ 1,200,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | 0 | [17] | 800,000 | [18] | 
| Investment, Identifier [Axis]: Salvo Technologies, Inc. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 1,225,000 | [19],[20] | $ 2,584,000 | [12],[14] | 
| Investment, Identifier [Axis]: Salvo Technologies, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 9.50% | [1],[2],[3],[5],[17] | 9.50% | [6],[7],[8],[10],[18],[21] | 
| Investment, interest rate, paid in cash |  | 14.80% | [1],[2],[3],[5],[17] | 12.50% | [6],[7],[8],[10],[18],[21] | 
| Investments, at fair value |  | $ 10,900,000 | [17] | $ 11,619,000 | [18],[21] | 
| Investment, Identifier [Axis]: Sea Link International IRB, Inc. – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 183,000 | [19],[20] | $ 153,000 | [12],[14] | 
| Investment, Identifier [Axis]: Sea Link International IRB, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in kind | [6],[7],[8],[10],[18],[30] |  |  | 14.50% |  | 
| Investments, at fair value | [18],[30] |  |  | $ 11,074,000 |  | 
| Investment, Identifier [Axis]: Sea Link International IRB, Inc. – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[28] | 11.30% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17],[28] | 2.00% |  |  |  | 
| Investments, at fair value | [17],[28] | $ 11,675,000 |  |  |  | 
| Investment, Identifier [Axis]: Sea Link International IRB, Inc. – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[28] | 12.00% |  |  |  | 
| Investment, interest rate, paid in kind | [1],[2],[3],[5],[17],[28] | 2.00% |  |  |  | 
| Investments, at fair value | [17],[28] | $ 4,000,000 |  |  |  | 
| Investment, Identifier [Axis]: Sea Link International IRB, Inc.– Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 340,000 | [19],[20] | 105,000 | [12],[14] | 
| Investment, Identifier [Axis]: Sokol & Company Holdings, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 1,612,000 | [19],[20] | $ 1,500,000 | [12],[14] | 
| Investment, Identifier [Axis]: Sokol & Company Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[21] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[21] |  |  | 10.00% |  | 
| Investments, at fair value | [18],[21] |  |  | $ 13,500,000 |  | 
| Investment, Identifier [Axis]: Sokol & Company Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.30% |  |  |  | 
| Investments, at fair value | [17] | $ 13,095,000 |  |  |  | 
| Investment, Identifier [Axis]: SpaceCo Holdings, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.20% | [1],[2],[3],[5],[17],[24] | 7.00% | [6],[7],[8],[10],[18],[25] | 
| Investment, interest rate, paid in cash |  | 12.50% | [1],[2],[3],[5],[17],[24] | 10.80% | [6],[7],[8],[10],[18],[25] | 
| Line of credit facility, available |  | $ 550,000 | [1],[2],[3],[5],[17],[24] | $ 100,000 | [6],[7],[8],[10],[18],[25] | 
| Investments, at fair value |  | $ 1,434,000 | [17],[24] | $ 1,886,000 | [18],[25] | 
| Investment, Identifier [Axis]: SpaceCo Holdings, LLC – Term Deb |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[25] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[25] |  |  | 10.80% |  | 
| Investments, at fair value | [18],[25] |  |  | $ 31,481,000 |  | 
| Investment, Identifier [Axis]: SpaceCo Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17],[24] | 7.20% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[24] | 12.50% |  |  |  | 
| Investments, at fair value | [17],[24] | $ 29,944,000 |  |  |  | 
| Investment, Identifier [Axis]: Springfield, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 10.10% | [1],[2],[3],[5],[17] | 10.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 15.40% | [1],[2],[3],[5],[17] | 13.10% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 29,850,000 | [17] | $ 29,738,000 | [18] | 
| Investment, Identifier [Axis]: TNCP Intermediate HoldCo, LLC – Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 3,073,000 | [19],[20] | $ 2,337,000 | [12],[14] | 
| Investment, Identifier [Axis]: TNCP Intermediate HoldCo, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14],[30] |  |  | 8.00% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[14],[30] |  |  | $ 1,000,000 |  | 
| Investments, at fair value |  | $ 900,000 | [19],[28] | 1,000,000 | [14],[30] | 
| Investment, Identifier [Axis]: TNCP Intermediate HoldCo, LLC—-Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[19],[28] | 8.00% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[19],[28] | $ 1,100,000 |  |  |  | 
| Investments, at fair value |  | 900,000 |  | 1,000,000 |  | 
| Investment, Identifier [Axis]: TNCP Intermediate HoldCo, LLC—Common Equity Units |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 3,073,000 |  | $ 2,337,000 |  | 
| Investment, Identifier [Axis]: Tailwind Smith Cooper Intermediate Corporation – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 9.00% | [1],[2],[3],[5],[15],[24] | 9.00% | [6],[7],[8],[10],[16] | 
| Investment, interest rate, paid in cash |  | 14.40% | [1],[2],[3],[5],[15],[24] | 12.10% | [6],[7],[8],[10],[16] | 
| Investments, at fair value |  | $ 4,294,000 | [15],[24] | $ 4,313,000 | [16] | 
| Investment, Identifier [Axis]: Targus Cayman HoldCo, Ltd. – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[36],[37] |  |  | 7,978,000 |  | 
| Investment, Identifier [Axis]: Technical Resource Management, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 1,415,000 |  |  |  | 
| Investment, Identifier [Axis]: Technical Resource Management, LLC – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 8.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 13.30% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 2,500,000 |  |  |  | 
| Investments, at fair value | [17] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: Technical Resource Management, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 8.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 13.30% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 1,000,000 |  |  |  | 
| Investments, at fair value | [17] | $ 1,970,000 |  |  |  | 
| Investment, Identifier [Axis]: Technical Resource Management, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 8.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 13.30% |  |  |  | 
| Investments, at fair value | [17] | $ 22,655,000 |  |  |  | 
| Investment, Identifier [Axis]: Total Safety Holdings, LLC – Common Equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 146,000 | [19],[20] | 50,000 | [12],[14] | 
| Investment, Identifier [Axis]: Triple H Food Processors, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 1,641,000 | [19],[20] | 672,000 | [12],[14] | 
| Investment, Identifier [Axis]: Triple H Food Processors, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 141,000 | [19],[20] | $ 120,000 | [12],[14] | 
| Investment, Identifier [Axis]: Trowbridge Chicago, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.30% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 2,000,000 |  |  |  | 
| Investments, at fair value | [17] | 0 |  |  |  | 
| Investment, Identifier [Axis]: Trowbridge Chicago, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 750,000 |  |  |  | 
| Investment, Identifier [Axis]: Trowbridge Chicago, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.00% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.30% |  |  |  | 
| Investments, at fair value | [17] | $ 5,664,000 |  |  |  | 
| Investment, Identifier [Axis]: Turn Key Health Clinics, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.30% | [1],[2],[3],[5],[17] | 7.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.60% | [1],[2],[3],[5],[17] | 10.40% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 1,500,000 | [1],[2],[3],[5],[17] | $ 1,500,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 499,000 | [17] | $ 495,000 | [18] | 
| Investment, Identifier [Axis]: Turn Key Health Clinics, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.30% | [1],[2],[3],[5],[17] | 7.30% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.60% | [1],[2],[3],[5],[17] | 10.40% | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 10,986,000 | [17] | $ 10,890,000 | [18] | 
| Investment, Identifier [Axis]: Unirac Holdings, Inc. – Delayed Draw Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 6.50% | [1],[2],[3],[5],[17] | 6.50% | [6],[7],[8],[10],[18],[21] | 
| Investment, interest rate, paid in cash |  | 11.80% | [1],[2],[3],[5],[17] | 9.50% | [6],[7],[8],[10],[18],[21] | 
| Line of credit facility, available |  | $ 1,669,000 | [1],[2],[3],[5],[17] | $ 2,778,000 | [6],[7],[8],[10],[18],[21] | 
| Investments, at fair value |  | $ 1,111,000 | [17] | $ 0 | [18],[21] | 
| Investment, Identifier [Axis]: Unirac Holdings, Inc. – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 6.50% | [1],[2],[3],[5],[17] | 6.50% | [6],[7],[8],[10],[18],[21] | 
| Investment, interest rate, paid in cash |  | 11.80% | [1],[2],[3],[5],[17] | 9.50% | [6],[7],[8],[10],[18],[21] | 
| Line of credit facility, available |  | $ 1,244,000 | [1],[2],[3],[5],[17] | $ 2,222,000 | [6],[7],[8],[10],[18],[21] | 
| Investments, at fair value |  | $ 980,000 | [17] | $ 0 | [18],[21] | 
| Investment, Identifier [Axis]: Unirac Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 6.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 11.80% |  |  |  | 
| Investments, at fair value | [17] | $ 14,925,000 |  |  |  | 
| Investment, Identifier [Axis]: Unirac Holdings, Inc. – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[21] |  |  | 6.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[21] |  |  | 9.50% |  | 
| Investments, at fair value | [18],[21] |  |  | $ 15,000,000 |  | 
| Investment, Identifier [Axis]: Viva Railings, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 7.10% | [1],[2],[3],[5],[17] | 7.00% | [6],[7],[8],[10],[18] | 
| Investment, interest rate, paid in cash |  | 12.40% | [1],[2],[3],[5],[17] | 10.10% | [6],[7],[8],[10],[18] | 
| Line of credit facility, available |  | $ 4,000,000 | [1],[2],[3],[5],[17] | $ 4,000,000 | [6],[7],[8],[10],[18] | 
| Investments, at fair value |  | $ 0 | [17] | $ 0 | [18] | 
| Investment, Identifier [Axis]: Viva Railings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 7.10% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 12.40% |  |  |  | 
| Investments, at fair value | [17] | $ 20,436,000 |  |  |  | 
| Investment, Identifier [Axis]: Viva Railings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18] |  |  | 7.00% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18] |  |  | 10.10% |  | 
| Investments, at fair value | [18] |  |  | $ 21,364,000 |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC - Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [12],[14] |  |  | 5,687,000 |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC - Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 0 |  | $ 5,687,000 |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread |  | 10.50% | [1],[2],[3],[5],[19] | 10.50% | [6],[7],[8],[10],[14] | 
| Investment, interest rate, paid in cash |  | 15.80% | [1],[2],[3],[5],[19] | 13.60% | [6],[7],[8],[10],[14] | 
| Line of credit facility, available |  | $ 32,000 | [1],[2],[3],[5],[19] | $ 32,000 | [6],[7],[8],[10],[14] | 
| Investments, at fair value |  | 1,468,000 | [19] | $ 1,468,000 | [14] | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC – Preferred Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value | [19],[20] | $ 0 |  |  |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[19] | 10.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[19] | 15.80% |  |  |  | 
| Investments, at fair value | [19] | $ 9,825,000 |  |  |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[14] |  |  | 10.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[14] |  |  | 13.60% |  | 
| Investments, at fair value | [14] |  |  | $ 9,925,000 |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC—Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 1,468,000 |  | 1,468,000 |  | 
| Investment, Identifier [Axis]: WB Xcel Holdings, LLC—Term Loan |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 9,825,000 |  | 9,925,000 |  | 
| Investment, Identifier [Axis]: WorkforceQA, LLC – Common Stock |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 359,000 | [19],[20] | $ 456,000 | [12],[14] | 
| Investment, Identifier [Axis]: WorkforceQA, LLC – Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17] | 6.50% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17] | 11.80% |  |  |  | 
| Line of credit facility, available | [1],[2],[3],[5],[17] | $ 1,600,000 |  |  |  | 
| Investments, at fair value | [17] | $ 400,000 |  |  |  | 
| Investment, Identifier [Axis]: WorkforceQA, LLC – Term Debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[25],[38] |  |  | 8.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[25],[38] |  |  | 11.60% |  | 
| Investments, at fair value | [18],[25],[38] |  |  | $ 9,975,000 |  | 
| Investment, Identifier [Axis]: WorkforceQA, LLC – Term Debt 1 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17],[39] | 8.40% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[39] | 13.70% |  |  |  | 
| Investments, at fair value | [17],[39] | $ 9,987,000 |  |  |  | 
| Investment, Identifier [Axis]: WorkforceQA, LLC – Term Debt 2 |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [1],[2],[3],[5],[17],[39] | 9.30% |  |  |  | 
| Investment, interest rate, paid in cash | [1],[2],[3],[5],[17],[39] | 14.60% |  |  |  | 
| Investments, at fair value | [17],[39] | $ 1,598,000 |  |  |  | 
| Investment, Identifier [Axis]: WorkforceQA, LLC– Line of Credit |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment, reference rate and spread | [6],[7],[8],[10],[18],[25] |  |  | 6.50% |  | 
| Investment, interest rate, paid in cash | [6],[7],[8],[10],[18],[25] |  |  | 9.60% |  | 
| Line of credit facility, available | [6],[7],[8],[10],[18],[25] |  |  | $ 2,000,000 |  | 
| Investments, at fair value | [18],[25] |  |  | 0 |  | 
| Aerospace and Defense |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 97,836,000 |  | 88,649,000 |  | 
| Beverage, Food, and Tobacco |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 78,788,000 |  | 64,283,000 |  | 
| Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 158,061,000 |  | 114,105,000 |  | 
| Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 135,060,000 |  | 148,907,000 |  | 
| Healthcare, Education, and Childcare |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 146,438,000 |  | 136,401,000 |  | 
| Machinery |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 6,411,000 |  | 9,562,000 |  | 
| Telecommunications |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 5,868,000 |  | 10,088,000 |  | 
| Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 27,571,000 |  | 20,144,000 |  | 
| Oil and Gas |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 27,830,000 |  | 25,373,000 |  | 
| Textiles and Leather |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 0 |  | 7,978,000 |  | 
| Secured first lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 510,701,000 |  | 463,858,000 |  | 
| Secured second lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 127,854,000 |  | 115,928,000 |  | 
| Unsecured debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 24,000 |  | 55,000 |  | 
| Preferred equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | 26,855,000 |  | 27,046,000 |  | 
| Common equity/equivalents |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investments, at fair value |  | $ 39,381,000 |  | $ 42,728,000 |  | 
| Non-Control/Non-Affiliate investments |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 162.40% | [1],[2],[3],[5],[40] | 182.20% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 663,544,000 | [40] | $ 574,811,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 120.30% | [1],[2],[3],[5],[40] | 131.20% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 491,686,000 | [40] | $ 413,631,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Aerospace and Defense |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 19.30% | [1],[2],[3],[5],[40] | 23.40% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 78,720,000 | [40] | $ 73,898,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Beverage, Food, and Tobacco |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 17.80% | [1],[2],[3],[5],[40] | 18.70% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 72,868,000 | [40] | $ 58,971,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Buildings and Real Estate |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.50% | [1],[2],[3],[5],[40] | 0.50% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 2,150,000 | [40] | $ 1,654,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 27.90% | [1],[2],[3],[5],[40] | 22.30% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 113,878,000 | [40] | $ 70,117,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 25.50% | [1],[2],[3],[5],[40] | 31.10% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 104,293,000 | [40] | $ 97,884,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Healthcare, Education, and Childcare |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 26.50% | [1],[2],[3],[5],[40] | 31.30% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 108,185,000 | [40] | $ 98,881,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Machinery |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.40% | [1],[2],[3],[5],[40] | 1.70% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 5,724,000 | [40] | $ 5,350,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Telecommunications |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.40% | [1],[2],[3],[5],[40] | 2.20% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 5,868,000 | [40] | $ 6,876,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured first lien debt | Printing and Publishing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets | [6],[7],[8],[10],[41] |  |  | 0.00% |  | 
| Non-Control/Non-Affiliate investments | Secured second lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 29.50% | [1],[2],[3],[5],[40] | 34.30% | [6],[7],[8],[10],[41] | 
| Investments, at fair value | [41] |  |  | $ 108,263,000 |  | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Beverage, Food, and Tobacco |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.60% | [1],[2],[3],[5],[40] | 1.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 8.90% | [1],[2],[3],[5],[40] | 10.80% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 36,136,000 | [40] | $ 34,051,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 4.00% | [1],[2],[3],[5],[40] | 2.30% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 16,465,000 | [40] | $ 7,265,000 | [41] | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Healthcare, Education, and Childcare |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 7.10% | [1],[2],[3],[5],[40] | 9.10% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Machinery |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets | [6],[7],[8],[10],[41] |  |  | 0.20% |  | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 3.80% | [1],[2],[3],[5],[40] | 3.50% | [6],[7],[8],[10],[41] | 
| Investments, at fair value | [40] | $ 15,675,000 |  |  |  | 
| Non-Control/Non-Affiliate investments | Secured second lien debt | Oil and Gas |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 5.10% | [1],[2],[3],[5],[40] | 7.40% | [6],[7],[8],[10],[41] | 
| Investments, at fair value | [40] | $ 120,429,000 |  |  |  | 
| Non-Control/Non-Affiliate investments | Unsecured debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Unsecured debt | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% |  | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 5.30% | [1],[2],[3],[5],[40] | 5.60% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 21,733,000 | [40] | $ 17,719,000 | [41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Beverage, Food, and Tobacco |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Buildings and Real Estate |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.10% | [1],[2],[3],[5],[40] | 0.20% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.30% | [1],[2],[3],[5],[40] | 0.80% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 2.40% | [1],[2],[3],[5],[40] | 2.60% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 9,654,000 | [40] | $ 8,151,000 | [41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Healthcare, Education, and Childcare |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.80% | [1],[2],[3],[5],[40] | 0.30% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Telecommunications |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 1.10% | [6],[7],[8],[10],[41] | 
| Investments, at fair value | [41] |  |  | $ 3,187,000 |  | 
| Non-Control/Non-Affiliate investments | Preferred equity | Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Preferred equity | Oil and Gas |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.70% | [1],[2],[3],[5],[40] | 0.60% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 6,826,000 | [40] | $ 2,028,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 7.30% | [1],[2],[3],[5],[40] | 11.10% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 29,672,000 | [40] | $ 35,143,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Aerospace and Defense |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 4.70% | [1],[2],[3],[5],[40] | 4.70% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 19,116,000 | [40] | $ 14,751,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Beverage, Food, and Tobacco |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.80% | [1],[2],[3],[5],[40] | 0.70% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 3,284,000 | [40] | $ 2,172,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Buildings and Real Estate |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.60% | [6],[7],[8],[10],[41] | 
| Investments, at fair value | [40] | $ 0 |  |  |  | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.10% | [1],[2],[3],[5],[40] | 0.10% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Healthcare, Education, and Childcare |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.50% | [1],[2],[3],[5],[40] | 2.50% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 6,002,000 | [40] | $ 7,775,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Machinery |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.10% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Telecommunications |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.10% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Oil and Gas |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Investments, at fair value |  | $ 146,000 | [40] | $ 50,000 | [41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Personal and Non-Durable Consumer Products (Manufacturing Only) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[40] | 0.00% | [6],[7],[8],[10],[41] | 
| Non-Control/Non-Affiliate investments | Common equity/equivalents | Textiles and Leather |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets | [6],[7],[8],[10],[41] |  |  | 2.50% |  | 
| Affiliate investments |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 2.60% | [1],[2],[3],[5],[42] | 12.40% | [6],[7],[8],[10],[43] | 
| Investments, at fair value |  | $ 10,421,000 | [42] | $ 39,091,000 | [43] | 
| Affiliate investments | Secured first lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.70% | [1],[2],[3],[5],[42] | 11.00% | [6],[7],[8],[10],[43] | 
| Investments, at fair value |  | $ 2,895,000 |  | $ 34,804,000 | [43] | 
| Affiliate investments | Secured first lien debt | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.70% |  | 0.80% | [6],[7],[8],[10],[43] | 
| Affiliate investments | Secured first lien debt | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% |  | 10.20% | [6],[7],[8],[10],[43] | 
| Investments, at fair value |  | $ 0 |  | $ 32,254,000 | [43] | 
| Affiliate investments | Preferred equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.30% | [1],[2],[3],[5],[42] | 1.20% | [6],[7],[8],[10],[43] | 
| Investments, at fair value |  | $ 5,122,000 | [42] | $ 3,640,000 | [43] | 
| Affiliate investments | Preferred equity | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[42] | 0.00% | [6],[7],[8],[10],[43] | 
| Affiliate investments | Preferred equity | Diversified/Conglomerate Service |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.10% | [1],[2],[3],[5],[42] | 0.90% | [6],[7],[8],[10],[43] | 
| Affiliate investments | Preferred equity | Personal and Non-Durable Consumer Products (Manufacturing Only) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.20% | [1],[2],[3],[5],[42] | 0.30% | [6],[7],[8],[10],[43] | 
| Affiliate investments | Common equity/equivalents |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.60% | [1],[2],[3],[5],[42] | 0.20% | [6],[7],[8],[10],[43] | 
| Investments, at fair value | [43] |  |  | $ 647,000 |  | 
| Affiliate investments | Common equity/equivalents | Personal and Non-Durable Consumer Products (Manufacturing Only) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.60% |  | 0.20% | [6],[7],[8],[10],[43] | 
| Control investments |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 7.50% | [1],[2],[3],[5],[44] | 11.30% | [6],[7],[8],[10],[45] | 
| Investments, at fair value |  | $ 30,850,000 | [44] | $ 35,713,000 | [45] | 
| Control investments | Secured first lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 3.90% | [1],[2],[3],[5],[44] | 4.90% | [6],[7],[8],[10],[45] | 
| Investments, at fair value |  | $ 16,120,000 | [44] | $ 15,423,000 |  | 
| Control investments | Secured first lien debt | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.90% | [1],[2],[3],[5],[44] | 1.00% | [6],[7],[8],[10],[45] | 
| Control investments | Secured first lien debt | Personal and Non-Durable Consumer Products (Manufacturing Only) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 2.80% | [1],[2],[3],[5],[44] | 3.60% | [6],[7],[8],[10],[45] | 
| Investments, at fair value |  | $ 11,293,000 | [44] | $ 11,393,000 | [45] | 
| Control investments | Secured first lien debt | Printing and Publishing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.20% | [1],[2],[3],[5],[44] | 0.30% | [6],[7],[8],[10],[45] | 
| Investments, at fair value | [45] |  |  | $ 15,423,000 |  | 
| Control investments | Secured second lien debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.80% | [1],[2],[3],[5],[44] | 2.40% | [6],[7],[8],[10],[45] | 
| Control investments | Secured second lien debt | Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.80% |  | 2.40% | [6],[7],[8],[10],[45] | 
| Control investments | Unsecured debt |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% |  | 0.00% | [6],[7],[8],[10],[45] | 
| Control investments | Unsecured debt | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% |  | 0.00% | [6],[7],[8],[10],[45] | 
| Control investments | Preferred equity |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[44] | 1.80% | [6],[7],[8],[10],[45] | 
| Control investments | Preferred equity | Personal and Non-Durable Consumer Products (Manufacturing Only) |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% |  | 1.80% | [6],[7],[8],[10],[45] | 
| Control investments | Common equity/equivalents |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.80% | [1],[2],[3],[5],[44] | 2.20% | [6],[7],[8],[10],[45] | 
| Investments, at fair value |  | $ 7,305,000 | [44] | $ 6,938,000 | [45] | 
| Control investments | Common equity/equivalents | Diversified/Conglomerate Manufacturing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.00% | [1],[2],[3],[5],[44] | 0.00% | [6],[7],[8],[10],[45] | 
| Investments, at fair value |  | $ 0 |  | $ 0 | [45] | 
| Control investments | Common equity/equivalents | Machinery |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.10% | [1],[2],[3],[5],[44] | 1.10% | [6],[7],[8],[10],[45] | 
| Control investments | Common equity/equivalents | Automobile |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 1.00% | [1],[2],[3],[5],[44] | 0.40% | [6],[7],[8],[10],[45] | 
| Control investments | Common equity/equivalents | Printing and Publishing |  |  |  |  |  | 
| Schedule of Investments [Line Items] |  |  |  |  |  | 
| Investment owned, percent of net assets |  | 0.70% | [1],[2],[3],[5],[44] | 0.70% |  | 
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