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Portfolio Company Investments - Schedule of Investments Type With Corresponding Percentage of Total Portfolio Investments (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 860,329 | $ 719,124
Percentage of Fair Value | 100.00% | 100.00%
Investments at cost | $ 828,693 | $ 621,786
Percentage of Cost | 100.00% | 100.00%
First Lien Debt |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 456,105 | $ 354,922
Percentage of Fair Value | 53.00% | 49.40%
Investments at cost | $ 453,585 | $ 353,306
Percentage of Cost | 54.70% | 56.80%
Second Lien Debt |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 182,948 | $ 158,815
Percentage of Fair Value | 21.30% | 22.10%
Investments at cost | $ 213,654 | $ 168,573
Percentage of Cost | 25.80% | 27.10%
Subordinated Debt |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 101,456 | $ 36,064
Percentage of Fair Value | 11.80% | 5.00%
Investments at cost | $ 100,634 | $ 35,995
Percentage of Cost | 12.10% | 5.80%
Equity |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 117,741 | $ 166,119
Percentage of Fair Value | 13.70% | 23.10%
Investments at cost | $ 57,868 | $ 60,589
Percentage of Cost | 7.00% | 9.80%
Warrants |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 2,079 | $ 3,204
Percentage of Fair Value | 0.20% | 0.40%
Investments at cost | $ 2,952 | $ 3,323
Percentage of Cost | 0.40% | 0.50%

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