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Portfolio Company Investments - Schedule of Portfolio Composition by Geographic Region at Fair Value and Cost and as Percentage of Total 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%
United States Midwest |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 180,556 | $ 157,222
Percentage of Fair Value | 21.00% | 21.90%
Investments at cost | $ 132,177 | $ 89,865
Percentage of Cost | 16.00% | 14.50%
United States Southeast |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 265,902 | $ 219,988
Percentage of Fair Value | 31.00% | 30.60%
Investments at cost | $ 258,373 | $ 197,380
Percentage of Cost | 31.10% | 31.70%
United States Northeast |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 127,427 | $ 126,569
Percentage of Fair Value | 14.80% | 17.60%
Investments at cost | $ 134,897 | $ 127,809
Percentage of Cost | 16.30% | 20.60%
United States West |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 151,487 | $ 105,918
Percentage of Fair Value | 17.60% | 14.70%
Investments at cost | $ 161,935 | $ 100,098
Percentage of Cost | 19.50% | 16.10%
United States Southwest |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 122,519 | $ 109,427
Percentage of Fair Value | 14.20% | 15.20%
Investments at cost | $ 128,873 | $ 106,634
Percentage of Cost | 15.60% | 17.10%
Canada |  |
Summary of Investment Holdings [Line Items] |  |
Investments at Fair Value | $ 12,438 |
Percentage of Fair Value | 1.40% |
Investments at cost | $ 12,438 |
Percentage of Cost | 1.50% |

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