SUMMARY OF PER SHARE INFORMATION (Details) - $ / shares	3 Months Ended				6 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Mar. 31, 2022
Per Share Data:
Investment income (in usd per share)	$ 0.96		$ 0.90		$ 1.84	$ 1.78
Operating expenses (in usd per share)	(0.42)		(0.45)		(0.81)	(0.89)
Income taxes (in usd per share)	(0.02)		(0.02)		(0.02)	(0.03)
Net investment income (in usd per share)	0.52		0.43		1.01	0.86
Net realized gain (loss), net of tax (in usd per share)	(0.31)		0.16		(0.24)	0.11
Net unrealized (depreciation) appreciation on investments, net of tax (in usd per share)	0.13		(0.03)		(0.32)	0.29
Realized loss on extinguishment of debt (in usd per share)	0		(0.76)		0	(0.78)
Total increase from investment operations (in usd per share)	0.34		(0.20)		0.45	0.48
Accretive effect of share issuances and repurchases (in usd per share)	0.13		0.47		0.39	0.95
Dividends to shareholders (in usd per share)	(0.50)	$ (0.63)	(0.54)	$ (0.53)	(1.13)	(1.07)
Issuance of restricted stock (in usd per share)	(0.01)		0		(0.14)	(0.10)
Common stock withheld for payroll taxes upon vesting of restricted stock (in usd per share)	0		0		(0.01)	(0.01)
Share based compensation expense (in usd per share)	0.04		0.04		0.07	0.09
Other (in usd per share)	(0.01)		0.01		0.04	0.01
(Decrease) increase in net asset value (in usd per share)	(0.01)		(0.22)		(0.33)	0.35
Net asset value
Beginning of period (in usd per share)	16.54	16.86	16.58	16.01	16.86	16.01
End of period (in usd per share)	$ 16.53	$ 16.54	$ 16.36	$ 16.58	$ 16.53	$ 16.36
Ratios and Supplemental Data
Ratio of operating expenses to average net assets	2.58%		2.72%		4.88%	5.37%
Ratio of net investment income to average net assets	3.15%		2.58%		6.03%	5.20%
Portfolio turnover	2.97%		8.43%		9.01%	9.66%
Total investment return	(5.32%)		10.72%		(24.06%)	18.66%
Total return based on change in NAV	2.96%		1.93%		4.74%	8.87%
Per share market value at the end of the period (in usd per share)	$ 16.94		$ 25.18		$ 16.94	$ 25.18
Weighted-average common and fully diluted shares outstanding (in shares)	27,987,699		22,534,443		26,757,376	21,871,805
Weighted average shares outstanding – basic (in share)	27,987,699		22,534,443		26,757,376	21,871,805
Common shares outstanding at end of period (in shares)	28,782,062		23,341,000		28,782,062	23,341,000	24,958,520