CONSOLIDATED STATEMENTS OF CHANGES IN NET ASSETS - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Investment Company, Net Assets [Roll Forward]
Number of shares, beginning balance (in shares)	36,076,425
Beginning balance	$ 590,408	$ 420,867
Number of shares, beginning balance (in shares)	2,339,512
Issuance of common stock	$ 44,872	46,035
Cancellation of treasury stock	0
Share-based compensation	963	821
Issuance of common stock under restricted stock plan, net of forfeitures	0	0
Common stock withheld for payroll taxes upon vesting of restricted stock	(926)	(641)
Dividends to shareholders	(22,916)	(16,615)
Change in restoration plan liability	(12)	8
Reclassification for certain permanent book-to-tax differences	0	0
Net increase resulting from operations	$ 23,812	$ 2,510
Number of shares, ending balance (in shares)	38,839,918	27,391,000
Ending balance	$ 636,201	$ 452,985
Number of shares, ending balance (in shares)	0
Common Stock
Investment Company, Net Assets [Roll Forward]
Number of shares, beginning balance (in shares)	36,076,425	24,958,520
Beginning balance	$ 9,604	$ 6,825
Issuance of common stock (in shares)	2,527,458	2,262,852
Issuance of common stock	$ 632	$ 566
Cancellation of treasury stock	$ (585)
Issuance of common stock under restricted stock plan, net of forfeitures (in shares)	282,616	199,042
Issuance of common stock under restricted stock plan, net of forfeitures	$ 71	$ 49
Common stock withheld for payroll taxes upon vesting of restricted stock (in shares)	(46,581)	(29,673)
Common stock withheld for payroll taxes upon vesting of restricted stock	$ (12)	$ (7)
Number of shares, ending balance (in shares)	38,839,918	27,390,741
Ending balance	$ 9,710	$ 7,433
Treasury Stock
Investment Company, Net Assets [Roll Forward]
Beginning balance	$ (23,937)	$ (23,937)
Number of shares, beginning balance (in shares)	2,339,512	2,339,512
Cancellation of treasury stock (in shares)	(2,339,512)
Cancellation of treasury stock	$ 23,937
Ending balance	$ 0	$ (23,937)
Number of shares, ending balance (in shares)	0	2,339,512
Additional Paid-In Capital
Investment Company, Net Assets [Roll Forward]
Beginning balance	$ 646,586	$ 448,235
Issuance of common stock	44,240	45,469
Cancellation of treasury stock	(23,352)
Share-based compensation	963	821
Issuance of common stock under restricted stock plan, net of forfeitures	(71)	(49)
Common stock withheld for payroll taxes upon vesting of restricted stock	(914)	(634)
Change in restoration plan liability	(12)	8
Reclassification for certain permanent book-to-tax differences		1
Ending balance	667,440	493,851
Total Distributable Earnings (Loss)
Investment Company, Net Assets [Roll Forward]
Beginning balance	(41,845)	(10,256)
Dividends to shareholders	(22,916)	(16,615)
Reclassification for certain permanent book-to-tax differences		(1)
Net increase resulting from operations	23,812	2,510
Ending balance	$ (40,949)	$ (24,362)