STATEMENTS OF ASSETS AND LIABILITIES (Parenthetical) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Investment cost	$ 2,591,761	$ 2,607,174
Foreign currencies, cost	$ 418	$ 2,404
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	130,000,000	130,000,000
Common stock, shares issued	65,451,359	65,451,359
Common stock, shares outstanding	65,451,359	65,451,359
Non-controlled/Non-affiliated Investments
Investment cost	$ 2,065,947	$ 2,019,573
Non-controlled/Affiliated Investments
Investment cost	121,409	121,307
Controlled Investments
Investment cost	$ 404,405	$ 466,294

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