Financial Highlights - Schedule of Financial Highlights (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021
Investment Company Financial Highlights [Abstract]
Net asset value at beginning of period			$ 15.79	$ 15.88
Net investment income			0.72	0.72
Net realized and change in unrealized gains (losses)			(0.38)	0.17
Net increase in net assets resulting from operations			0.34	0.88
Distribution of net investment income			(0.68)	(0.72)
Distribution of return of capital			0	0
Accretion due to share repurchases			0.01	0.02
Net asset value at end of period	$ 15.45	$ 16.07	15.45	16.07
Per share market value at end of period	$ 10.22	$ 12.97	$ 10.22	$ 12.97
Total return			(17.79%)	(0.37%)
Shares outstanding at end of period	65,451,359	64,662,651	65,451,359	64,662,651	63,518,718	63,647,240	65,113,604	65,259,176
Weighted average shares outstanding	64,737,122	65,031,131	64,150,905	65,115,530
Net assets at end of period	$ 1,011,036	$ 1,039,133	$ 1,011,036	$ 1,039,133	$ 985,987	$ 1,004,832	$ 1,043,005	$ 1,036,330
Annualized ratio of operating expenses to average net assets			5.96%	5.81%
Annualized ratio of interest and other debt expenses to average net assets			7.23%	5.10%
Annualized ratio of total expenses to average net assets			13.19%	10.91%
Annualized ratio of net investment income to average net assets			9.20%	8.94%
Average debt outstanding	$ 1,539,332	$ 1,539,062	$ 1,579,696	$ 1,499,635
Average debt per share			$ 24.63	$ 23.03
Annualized portfolio turnover rate			27.05%	35.04%
Asset coverage per unit			$ 1,655	$ 1,648