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Asset coverage ratio.

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Line of credit facility, remaining unused capacity, commitment fee percentage.

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Percentage of public offering price.

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Prepayment of debentures.

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Secured borrowings.

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Senior asset coverage ratio.

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Underwriting discounts.

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Face (par) amount of debt instrument at time of issuance.

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

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Weighted average interest rate of debt outstanding.

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Debt - Additional Information (Details) - USD ($) $ in Thousands						3 Months Ended		12 Months Ended
	Aug. 17, 2022	Oct. 08, 2021	Dec. 23, 2020	Jun. 26, 2020	Apr. 24, 2019	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Debt instrument asset coverage percentage						272.10%		280.00%
Aggregate principal amount						$ 165,000		$ 153,000
Weighted average interest rate						4.244%	3.726%
Offering expenses						$ 9,552		9,776
Loss on extinguishment of debt							$ (198)
Secured borrowings						16,634		16,880
Aggregate amount of outstanding of senior securities						281,634		266,880
Fair value of loans included in investments						$ 16,630		16,875
Credit facility, interest rate per annum						0.97%	1.375%
SBA Debentures
Debt Instrument [Line Items]
Weighted average interest rate						3.268%	2.846%
Offering expenses						$ 4,648		$ 4,524
Prepayment of debentures						$ 0	$ 20,000
Debt instrument, maturity year range, start						2025	2025
Debt instrument, maturity year range, end						2028	2028
Loss on extinguishment of debt						$ 0	$ (198)
Debt instrument term						10 years
Interest rate payment term						semi-annually on March 1 and September 1
Unused commitments amount						$ 25,000			$ 37,000
Secured Borrowings
Debt Instrument [Line Items]
Weighted average interest rate						8.685%	4.497%	7.80%
4.75% Notes due 2026
Debt Instrument [Line Items]
Maturity date			Jan. 31, 2026
Aggregate principal amount			$ 125,000
Interest rate			4.75%
Net proceeds from the notes			$ 122,100
Underwriting discounts			$ 2,500
Percentage of public offering price			100.00%
Offering expenses			$ 400
Debt instrument, redemption description						The January 2026 Notes may be redeemed in whole or in part at any time or from time to time at our option subject to a make whole provision if redeemed more than three months prior to maturity and at par thereafter. Interest on the January 2026 Notes is payable on January 31 and July 31 of each year. The Company does not intend to list the January 2026 Notes on any securities exchange or automated dealer quotation system.
3.50% Notes Due 2026
Debt Instrument [Line Items]
Maturity date		Nov. 15, 2026
Aggregate principal amount		$ 125,000
Interest rate		3.50%
Net proceeds from the notes		$ 122,095
Underwriting discounts		$ 2,500
Percentage of public offering price		99.996%
Offering expenses		$ 400
Debt instrument, redemption description						The November 2026 Notes may be redeemed in whole or in part at any time or from time to time at our option subject to a make whole provision if redeemed more than three months prior to maturity and at par thereafter. Interest on the November 2026 Notes is payable on May 15 and November 15 of each year. The Company does not intend to list the November 2026 Notes on any securities exchange or automated dealer quotation system.
Revolving Credit Facility \| Credit Agreement \| ING Capital LLC
Debt Instrument [Line Items]
Maturity date	Aug. 17, 2027			Apr. 24, 2023
Interest rate after certain conditions satisfied	2.675%			2.50%
Asset coverage ratio	1.50%			2.00%
Senior asset coverage ratio	2.00%
Remaining unused portion of Credit Facility commitment percentage					0.50%
Performing first lien bank loans, minimum percentage					35.00%
Revolving Credit Facility \| Credit Agreement \| ING Capital LLC \| SOFR
Debt Instrument [Line Items]
Interest rate prior to certain conditions satisfied	3.00%			2.675%
Revolving Credit Facility \| Credit Agreement \| ING Capital LLC \| Maximum
Debt Instrument [Line Items]
Credit facility, interest rate per annum					2.675%
Credit facility commitment percentage					35.00%
Revolving Credit Facility \| Credit Agreement \| ING Capital LLC \| Minimum
Debt Instrument [Line Items]
Credit facility, interest rate per annum					2.50%