Borrowings - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Borrowings
Asset coverage ratio	163.00%	167.00%
Revolving credit facility	$ 321,700	$ 304,100
2026 Notes
Borrowings
Revolving credit facility	$ 130,000	$ 130,000
Interest rate	4.75%
Revolving credit facility
Borrowings
Maximum borrowing capacity	$ 255,000
Line of credit facility, accordion feature	$ 400,000
Maximum borrowing capacity, Percentage of the fair market value of its portfolio company investments	72.50%
Consolidated total net assets	$ 150,000
Consolidated total net assets, Percentage of net proceeds from sales of equity securities after March 1, 2019	65.00%
Percentage of distributions in cash or property other than common stock	115.00%
Interest rate, daily rate per annum	1.625%
Weighted average interest rate	8.10%	8.10%
Revolving credit facility \| Available maximum borrowing capacity percentage greater than 35%
Borrowings
Commitment fee (in percent)	0.50%
Available maximum borrowing capacity, percentage	35.00%
Revolving credit facility \| Available maximum borrowing capacity percentage equal to or less than 35%
Borrowings
Commitment fee (in percent)	1.00%
Available maximum borrowing capacity, percentage	35.00%
Revolving credit facility \| Secured Overnight Financing Rate (SOFR)
Borrowings
Interest rate, basis spread	2.625%
Interest rate, daily basis spread	1.00%
Interest rate, floor	0.50%
Revolving credit facility \| Prime Rate
Borrowings
Interest rate, daily basis spread	1.50%
Revolving credit facility \| Federal funds rate
Borrowings
Interest rate, daily basis spread	0.50%
Revolving credit facility \| Denominated in U.S. dollar
Borrowings
Borrowings	$ 191,700	$ 174,100
Revolving credit facility \| Minimum
Borrowings
Assets to debt ratio	1.5
Senior debt coverage ratio	2

Percentage of asset coverage ratio based on aggregate borrowings outstanding.

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A ratio of total assets (less total liabilities other than indebtedness) to total indebtedness.

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Amount of consolidated net assets.

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Percentage of net proceeds from sale of equity securities considered for consolidated total net assets.

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Debt Instrument, Daily Basis Spread on Variable Rate

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Daily rate per annum for funds borrowed, under the debt agreement.

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Floor rate for a debt instrument.

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Percentage of distributions in cash or property other than common stock.

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Line of Credit Facility, Accordion Feature, Increase Limit

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Percentage of maximum amount of borrowing capacity under a line of credit that is available.

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Percentage of maximum borrowing capacity on fair market value of its portfolio company investments under line of credit facility.

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A ratio of net revenue to annual debt service in respect of all senior lien obligations .

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Weighted average interest rate of debt outstanding.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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