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Portfolio Company Investments - Additional Information (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) Investment | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) Investment
Investment Holdings [Line Items] |  |  |
Number of investment portfolio companies | Investment | 78 |  | 76
Number of residual investment porfolio companies | Investment | 2 |  | 2
Aggregate fair value of total portfolio | $ | $ 897,324 |  | $ 860,329
Weighted average effective yield investment percentage | 14.30% |  | 13.80%
Average fully diluted equity ownership percentage | 3.90% |  | 4.00%
Percentage of equity investments held in portfolio companies | 76.30% |  | 74.40%
Purchases of debt and equity investments | $ | $ 51,521 | $ 114,428 |
Proceeds from sales and repayments | $ | $ 15,918 | $ 23,185 |
Number of investments represented more than ten percentage of aggregate investment portfolio | Investment | 0 |  | 0
Debt investments in portfolio companies on non-accrual status | Investment | 5 |  | 4
Pfanstiehl, Inc |  |  |
Investment Holdings [Line Items] |  |  |
Investment | $ | $ 50,975 |  | $ 51,992
Investments as percentage of total assets | 5.40% |  | 5.60%
Maximum |  |  |
Investment Holdings [Line Items] |  |  |
Investment maturity period | 7 years |  |
Minimum |  |  |
Investment Holdings [Line Items] |  |  |
Investment maturity period | 5 years |  |

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