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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Debt investment in number of portfolio companies on non-accrual status.

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Investments as percentage of assets.

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Number of investment porfolio companies.

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Number of Investments represented more than ten percentage of aggregate investment portfolio.

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Number of residual investment porfolio companies.

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Percentage of equity investments held in portfolio companies.

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Proceeds from sales and repayments including principal return of capital distributions and realized gains.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Weighted average yield of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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