Portfolio Company Investments - Additional Information (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022 USD ($) Investment	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) Investment
Investment Holdings [Line Items]
Number of investment portfolio companies \| Investment	75		70
Number of residual investment porfolio companies \| Investment	13		8
Aggregate fair value of total portfolio \| $	$ 856,914		$ 719,124
Weighted average effective yield investment percentage	12.90%		12.30%
Average fully diluted equity ownership percentage	3.70%		4.70%
Percentage of equity investments held in portfolio companies	77.30%		82.10%
Purchases of debt and equity investments \| $	$ 267,950	$ 245,544
Proceeds from sales and repayments \| $	$ 128,255	$ 319,036
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	3		1
Pfanstiehl, Inc
Investment Holdings [Line Items]
Investment \| $	$ 51,796		$ 57,639
Investments as percentage of total assets	5.70%		6.40%
Maximum
Investment Holdings [Line Items]
Investment maturity period	7 years
Minimum
Investment Holdings [Line Items]
Investment maturity period	5 years

Average fully diluted equity ownership Percentage.

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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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Sum of the carrying amounts as of the balance sheet date of all investments.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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