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INVESTMENTS - Investment Portfolio, at Fair Value and Cost (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 | Mar. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 1,150,046 | [1],[2],[3] | $ 936,614 | [4],[5],[6]
Percent of net assets | 204.80% | [1],[2] | 222.50% |
Cost | $ 1,159,712 | [1],[2],[7],[8] | $ 938,303 | [4],[5],[9],[10]
Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 100.00% |  | 100.00% |
First lien loans |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 954,000 |  | $ 739,872 |
Percent of net assets | 169.90% |  | 175.80% |
Cost | $ 968,597 |  | $ 745,290 |
First lien loans | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 83.00% |  | 79.00% |
First lien loans | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 83.50% |  | 79.40% |
Second lien loans |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 35,446 |  | $ 52,645 |
Percent of net assets | 6.30% |  | 12.50% |
Cost | $ 44,050 |  | $ 55,976 |
Second lien loans | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.10% |  | 5.60% |
Second lien loans | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.80% |  | 6.00% |
Subordinated debt |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 852 |  | $ 1,317 |
Percent of net assets | 0.10% |  | 0.30% |
Cost | $ 754 |  | $ 994 |
Subordinated debt | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.10% |  | 0.10% |
Subordinated debt | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.10% |  | 0.10% |
Preferred equity |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 61,283 |  | $ 44,663 |
Percent of net assets | 10.90% |  | 10.60% |
Cost | $ 39,416 |  | $ 25,544 |
Preferred equity | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 5.30% |  | 4.80% |
Preferred equity | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.40% |  | 2.70% |
Common equity & warrants |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 50,840 |  | $ 40,514 |
Percent of net assets | 9.10% |  | 9.60% |
Cost | $ 30,895 |  | $ 34,499 |
Common equity & warrants | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 4.40% |  | 4.30% |
Common equity & warrants | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.70% |  | 3.70% |
I-45 SLF LLC |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 47,625 |  | $ 57,603 |
Percent of net assets | 8.50% |  | 13.70% |
Cost | $ 76,000 |  | $ 76,000 |
I-45 SLF LLC | Percentage of Total Portfolio at Fair Value | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 4.10% |  | 6.20% |
I-45 SLF LLC | Percentage of Total Portfolio at Cost | Investment Type |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 6.50% |  | 8.10% |
Southeast |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 239,539 |  | $ 136,588 |
Percent of net assets | 42.70% |  | 32.50% |
Cost | $ 236,922 |  | $ 138,929 |
Southeast | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 20.80% |  | 14.60% |
Southeast | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 20.40% |  | 14.90% |
Northeast |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 230,643 |  | $ 225,578 |
Percent of net assets | 41.10% |  | 53.60% |
Cost | $ 222,894 |  | $ 221,780 |
Northeast | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 20.10% |  | 24.10% |
Northeast | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 19.20% |  | 23.60% |
West |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 228,254 |  | $ 163,924 |
Percent of net assets | 40.60% |  | 38.90% |
Cost | $ 223,761 |  | $ 153,292 |
West | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 19.80% |  | 17.50% |
West | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 19.30% |  | 16.30% |
Southwest |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 222,872 |  | $ 206,057 |
Percent of net assets | 39.70% |  | 49.00% |
Cost | $ 218,712 |  | $ 204,443 |
Southwest | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 19.40% |  | 22.00% |
Southwest | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 18.80% |  | 21.80% |
Midwest |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 155,675 |  | $ 132,308 |
Percent of net assets | 27.70% |  | 31.40% |
Cost | $ 157,333 |  | $ 129,354 |
Midwest | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 13.60% |  | 14.10% |
Midwest | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 13.60% |  | 13.80% |
I-45 SLF LLC |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 47,625 |  | $ 57,603 |
Percent of net assets | 8.50% |  | 13.70% |
Cost | $ 76,000 |  | $ 76,000 |
I-45 SLF LLC | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 4.10% |  | 6.10% |
I-45 SLF LLC | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 6.60% |  | 8.10% |
International |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 25,438 |  | $ 14,556 |
Percent of net assets | 4.50% |  | 3.40% |
Cost | $ 24,090 |  | $ 14,505 |
International | Percentage of Total Portfolio at Fair Value | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.20% |  | 1.60% |
International | Percentage of Total Portfolio at Cost | Geographic |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.10% |  | 1.50% |
Media & Marketing |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 142,382 |  | $ 43,463 |
Percent of net assets | 25.40% |  | 10.30% |
Cost | $ 132,117 |  | $ 33,049 |
Media & Marketing | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 12.40% |  | 4.60% |
Media & Marketing | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 11.40% |  | 3.50% |
Business Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 127,741 |  | $ 123,697 |
Percent of net assets | 22.70% |  | 29.40% |
Cost | $ 128,237 |  | $ 124,860 |
Business Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 11.10% |  | 13.20% |
Business Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 11.10% |  | 13.30% |
Healthcare Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 108,710 |  | $ 88,131 |
Percent of net assets | 19.40% |  | 21.00% |
Cost | $ 123,408 |  | $ 96,946 |
Healthcare Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 9.50% |  | 9.40% |
Healthcare Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 10.60% |  | 10.30% |
Consumer Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 90,019 |  | $ 71,730 |
Percent of net assets | 15.90% |  | 17.00% |
Cost | $ 89,283 |  | $ 71,203 |
Consumer Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 7.80% |  | 7.70% |
Consumer Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 7.70% |  | 7.60% |
Consumer Products & Retail |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 86,771 |  | $ 90,457 |
Percent of net assets | 15.40% |  | 21.50% |
Cost | $ 86,298 |  | $ 88,375 |
Consumer Products & Retail | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 7.50% |  | 9.70% |
Consumer Products & Retail | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 7.40% |  | 9.40% |
Food, Agriculture & Beverage |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 72,803 |  | $ 48,876 |
Percent of net assets | 13.00% |  | 11.60% |
Cost | $ 74,059 |  | $ 47,057 |
Food, Agriculture & Beverage | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 6.30% |  | 5.20% |
Food, Agriculture & Beverage | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 6.40% |  | 5.00% |
Healthcare Products |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 67,002 |  | $ 32,054 |
Percent of net assets | 11.90% |  | 7.60% |
Cost | $ 67,777 |  | $ 33,018 |
Healthcare Products | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 5.80% |  | 3.40% |
Healthcare Products | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 5.80% |  | 3.50% |
Technology Products & Components |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 64,199 |  | $ 37,047 |
Percent of net assets | 11.40% |  | 8.80% |
Cost | $ 46,947 |  | $ 30,440 |
Technology Products & Components | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 5.60% |  | 4.00% |
Technology Products & Components | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 4.10% |  | 3.30% |
I-45 SLF LLC |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 47,625 |  | $ 57,603 |
Percent of net assets | 8.50% |  | 13.70% |
Cost | $ 76,000 |  | $ 76,000 |
I-45 SLF LLC | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 4.10% |  | 6.20% |
I-45 SLF LLC | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 6.60% |  | 8.10% |
Transportation & Logistics |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 41,939 |  | $ 34,038 |
Percent of net assets | 7.50% |  | 8.10% |
Cost | $ 35,923 |  | $ 29,513 |
Transportation & Logistics | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.70% |  | 3.60% |
Transportation & Logistics | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.10% |  | 3.10% |
Financial Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 40,418 |  | $ 39,305 |
Percent of net assets | 7.20% |  | 9.30% |
Cost | $ 31,019 |  | $ 31,229 |
Financial Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.50% |  | 4.20% |
Financial Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.70% |  | 3.30% |
Software & IT Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 38,572 |  | $ 33,414 |
Percent of net assets | 6.90% |  | 7.90% |
Cost | $ 39,844 |  | $ 34,866 |
Software & IT Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.40% |  | 3.60% |
Software & IT Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.40% |  | 3.70% |
Distribution |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 34,100 |  | $ 54,798 |
Percent of net assets | 6.10% |  | 13.00% |
Cost | $ 35,904 |  | $ 54,035 |
Distribution | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.00% |  | 5.90% |
Distribution | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 3.10% |  | 5.80% |
Education |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 26,426 |  | $ 32,072 |
Percent of net assets | 4.70% |  | 7.60% |
Cost | $ 26,046 |  | $ 32,119 |
Education | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.30% |  | 3.40% |
Education | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.20% |  | 3.40% |
Industrial Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 26,233 |  | $ 11,614 |
Percent of net assets | 4.70% |  | 2.80% |
Cost | $ 25,900 |  | $ 11,451 |
Industrial Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.30% |  | 1.20% |
Industrial Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.20% |  | 1.20% |
Industrial Products |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 22,387 |  | $ 13,891 |
Percent of net assets | 4.00% |  | 3.30% |
Cost | $ 18,839 |  | $ 13,901 |
Industrial Products | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.00% |  | 1.50% |
Industrial Products | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.60% |  | 1.50% |
Energy Services (Midstream) |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 22,355 |  | $ 13,465 |
Percent of net assets | 4.00% |  | 3.20% |
Cost | $ 23,014 |  | $ 13,582 |
Energy Services (Midstream) | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.90% |  | 1.40% |
Energy Services (Midstream) | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.00% |  | 1.50% |
Environmental Services |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 19,592 |  | $ 20,641 |
Percent of net assets | 3.50% |  | 4.90% |
Cost | $ 24,920 |  | $ 23,108 |
Environmental Services | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.70% |  | 2.20% |
Environmental Services | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 2.20% |  | 2.50% |
Specialty Chemicals |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 17,884 |  | $ 17,749 |
Percent of net assets | 3.20% |  | 4.20% |
Cost | $ 17,559 |  | $ 17,640 |
Specialty Chemicals | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.60% |  | 1.90% |
Specialty Chemicals | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.50% |  | 1.90% |
Telecommunications |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 17,776 |  | $ 18,736 |
Percent of net assets | 3.20% |  | 4.50% |
Cost | $ 21,829 |  | $ 22,341 |
Telecommunications | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.50% |  | 2.00% |
Telecommunications | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.90% |  | 2.40% |
Energy Services (Upstream) |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 17,775 |  | $ 17,910 |
Percent of net assets | 3.20% |  | 4.30% |
Cost | $ 17,426 |  | $ 17,500 |
Energy Services (Upstream) | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.50% |  | 1.90% |
Energy Services (Upstream) | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 1.50% |  | 1.90% |
Containers & Packaging |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 10,537 |  | $ 10,671 |
Percent of net assets | 1.80% |  | 2.50% |
Cost | $ 10,672 |  | $ 10,723 |
Containers & Packaging | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.90% |  | 1.10% |
Containers & Packaging | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.90% |  | 1.10% |
Aerospace & Defense |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 6,800 |  | $ 6,800 |
Percent of net assets | 1.20% |  | 1.60% |
Cost | $ 6,691 |  | $ 6,672 |
Aerospace & Defense | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.60% |  | 0.70% |
Aerospace & Defense | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio | 0.60% |  | 0.70% |
Commodities & Mining |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value |  |  | $ 10,877 |
Percent of net assets |  |  | 2.60% |
Cost |  |  | $ 11,135 |
Commodities & Mining | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 1.20% |
Commodities & Mining | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 1.20% |
Restaurants |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value |  |  | $ 5,367 |
Percent of net assets |  |  | 1.30% |
Cost |  |  | $ 4,556 |
Restaurants | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 0.60% |
Restaurants | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 0.50% |
Paper & Forest Products |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value |  |  | $ 2,208 |
Percent of net assets |  |  | 0.50% |
Cost |  |  | $ 2,984 |
Paper & Forest Products | Percentage of Total Portfolio at Fair Value | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 0.20% |
Paper & Forest Products | Percentage of Total Portfolio at Cost | Industry |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Percentage of Total Portfolio |  |  | 0.30% |
First lien last out loans |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 51,000 |  | $ 38,600 |
Split lien term loans included in first lien loans |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | 37,200 |  | 36,400 |
Split lien term loans included in second lien loans |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | 20,600 |  | 33,900 |
Unsecured convertible Note |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Investments at fair value | $ 500 |  | $ 700 |
[1] | All debt investments are income-producing, unless otherwise noted. Equity investments are non-income producing, unless otherwise noted.
[2] | Equity ownership may be held in shares or units of a company that is either wholly owned by the portfolio company or under common control by the same parent company to the portfolio company.
[3] | The Company's investment portfolio is comprised entirely of debt and equity securities of privately held companies for which quoted prices falling within the categories of Level 1 and Level 2 inputs are not readily available. Therefore, the Company values all of its portfolio investments at fair value, as determined in good faith by the Board of Directors, using significant unobservable Level 3 inputs. Refer to Note 4 - Fair Value Measurements for further discussion.
[4] | All debt investments are income-producing, unless otherwise noted. Equity investments and warrants are non-income producing, unless otherwise noted.
[5] | Equity ownership may be held in shares or units of a company that is either wholly owned by the portfolio company or under common control by the same parent company to the portfolio company.
[6] | The Company's investment portfolio is comprised entirely of debt and equity securities of privately held companies for which quoted prices falling within the categories of Level 1 and Level 2 inputs are not readily available. Therefore, the Company values all of its portfolio investments at fair value, as determined in good faith by the Board of Directors, using significant unobservable Level 3 inputs. Refer to Note 4 for further discussion.
[7] | As of December 31, 2022, the cumulative gross unrealized appreciation for U.S. federal income tax purposes was approximately $66.9 million; cumulative gross unrealized depreciation for federal income tax purposes was $66.7 million. Cumulative net unrealized appreciation was $0.2 million, based on a tax cost of $1,150.6 million.
[8] | Negative cost in this column represents the original issue discount of certain undrawn revolvers and delayed draw term loans.
[9] | As of March 31, 2022, the cumulative gross unrealized appreciation for U.S. federal income tax purposes is approximately $67.8 million; cumulative gross unrealized depreciation for federal income tax purposes is $61.7 million. Cumulative net unrealized appreciation is $6.1 million, based on a tax cost of $852.4 million.
[10] | Represents amortized cost. Negative cost in this column represents the original issue discount of certain undrawn revolvers and delayed draw term loans.

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