Quarterly report pursuant to Section 13 or 15(d)

INVESTMENTS - Schedule of Investment Concentrations (Details)

v3.25.0.1
INVESTMENTS - Schedule of Investment Concentrations (Details) - USD ($)
$ in Thousands
 9 Months Ended 12 Months Ended
Dec. 31, 2024
Mar. 31, 2024
Summary of Investment Holdings [Line Items]    
Cost $ 1,021,741 $ 854,290 [1]
Fair Value 1,072,230 920,504 [1]
Northeast    
Summary of Investment Holdings [Line Items]    
Fair Value 305,374 207,870
South    
Summary of Investment Holdings [Line Items]    
Fair Value 295,954 346,838
Midwest    
Summary of Investment Holdings [Line Items]    
Fair Value 222,587 141,925
West    
Summary of Investment Holdings [Line Items]    
Fair Value 221,135 223,871
Canada    
Summary of Investment Holdings [Line Items]    
Fair Value 27,180 0
Diversified/Conglomerate Services    
Summary of Investment Holdings [Line Items]    
Fair Value 167,188 264,535
Home and Office Furnishings, Housewares, and Durable Consumer Products    
Summary of Investment Holdings [Line Items]    
Fair Value 164,017 160,038
Hotels, Motels, Inns, and Gaming    
Summary of Investment Holdings [Line Items]    
Fair Value 116,534 77,366
Aerospace and Defense    
Summary of Investment Holdings [Line Items]    
Fair Value 108,464 29,064
Machinery (Non-Agriculture, Non-Construction, and Non-Electronic)    
Summary of Investment Holdings [Line Items]    
Fair Value 100,919 92,781
Leisure, Amusement, Motion Pictures, and Entertainment    
Summary of Investment Holdings [Line Items]    
Fair Value 74,334 39,350
Electronics    
Summary of Investment Holdings [Line Items]    
Fair Value 71,321 0
Oil and Gas    
Summary of Investment Holdings [Line Items]    
Fair Value 67,775 51,171
Buildings and Real Estate    
Summary of Investment Holdings [Line Items]    
Fair Value 61,703 60,431
Healthcare, Education, and Childcare    
Summary of Investment Holdings [Line Items]    
Fair Value 44,131 49,638
Mining, Steel, Iron and Non-Precious Metals    
Summary of Investment Holdings [Line Items]    
Fair Value 35,586 30,537
Chemicals, Plastics, and Rubber    
Summary of Investment Holdings [Line Items]    
Fair Value 15,889 20,363
Printing and Publishing    
Summary of Investment Holdings [Line Items]    
Fair Value 14,400 14,238
Cargo Transport    
Summary of Investment Holdings [Line Items]    
Fair Value 12,514 13,500
Telecommunications    
Summary of Investment Holdings [Line Items]    
Fair Value 6,796 9,002
Other less than 2.0%    
Summary of Investment Holdings [Line Items]    
Fair Value $ 10,659 $ 8,490
Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 100.00% 100.00%
Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 100.00% 100.00%
Investment Owned, at Fair Value | Industry Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 100.00% 100.00%
Investment Owned, at Fair Value | Industry Concentration Risk | Diversified/Conglomerate Services    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 15.60% 28.70%
Investment Owned, at Fair Value | Industry Concentration Risk | Home and Office Furnishings, Housewares, and Durable Consumer Products    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 15.30% 17.30%
Investment Owned, at Fair Value | Industry Concentration Risk | Hotels, Motels, Inns, and Gaming    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 10.90% 8.40%
Investment Owned, at Fair Value | Industry Concentration Risk | Aerospace and Defense    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 10.10% 3.20%
Investment Owned, at Fair Value | Industry Concentration Risk | Machinery (Non-Agriculture, Non-Construction, and Non-Electronic)    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 9.40% 10.10%
Investment Owned, at Fair Value | Industry Concentration Risk | Leisure, Amusement, Motion Pictures, and Entertainment    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 6.90% 4.30%
Investment Owned, at Fair Value | Industry Concentration Risk | Electronics    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 6.70% 0.00%
Investment Owned, at Fair Value | Industry Concentration Risk | Oil and Gas    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 6.30% 5.60%
Investment Owned, at Fair Value | Industry Concentration Risk | Buildings and Real Estate    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 5.80% 6.60%
Investment Owned, at Fair Value | Industry Concentration Risk | Healthcare, Education, and Childcare    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 4.10% 5.40%
Investment Owned, at Fair Value | Industry Concentration Risk | Mining, Steel, Iron and Non-Precious Metals    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 3.30% 3.30%
Investment Owned, at Fair Value | Industry Concentration Risk | Chemicals, Plastics, and Rubber    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 1.50% 2.20%
Investment Owned, at Fair Value | Industry Concentration Risk | Printing and Publishing    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 1.30% 1.50%
Investment Owned, at Fair Value | Industry Concentration Risk | Cargo Transport    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 1.20% 1.50%
Investment Owned, at Fair Value | Industry Concentration Risk | Telecommunications    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 0.60% 1.00%
Investment Owned, at Fair Value | Industry Concentration Risk | Other less than 2.0%    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 1.00% 0.90%
Investment Owned, at Fair Value | Geographic Regions Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 100.00% 100.00%
Investment Owned, at Fair Value | Geographic Regions Risk | Northeast    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 28.50% 22.60%
Investment Owned, at Fair Value | Geographic Regions Risk | South    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 27.60% 37.70%
Investment Owned, at Fair Value | Geographic Regions Risk | Midwest    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 20.80% 15.40%
Investment Owned, at Fair Value | Geographic Regions Risk | West    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 20.60% 24.30%
Investment Owned, at Fair Value | Geographic Regions Risk | Canada    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 2.50% 0.00%
Total debt    
Summary of Investment Holdings [Line Items]    
Cost $ 780,457 $ 658,383
Fair Value $ 708,654 $ 613,559
Total debt | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 76.30% 77.00%
Total debt | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 66.00% 66.60%
Secured First Lien Debt    
Summary of Investment Holdings [Line Items]    
Cost $ 660,499 $ 513,425
Fair Value $ 599,911 $ 474,856
Secured First Lien Debt | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 64.60% 60.10%
Secured First Lien Debt | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 55.90% 51.60%
Secured Second Lien Debt    
Summary of Investment Holdings [Line Items]    
Cost $ 119,958 $ 144,958
Fair Value $ 108,743 $ 138,703
Secured Second Lien Debt | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 11.70% 16.90%
Secured Second Lien Debt | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 10.10% 15.00%
Total equity/equivalents    
Summary of Investment Holdings [Line Items]    
Cost $ 241,284 $ 195,907
Fair Value $ 363,576 $ 306,945
Total equity/equivalents | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 23.70% 23.00%
Total equity/equivalents | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 34.00% 33.40%
Preferred Equity    
Summary of Investment Holdings [Line Items]    
Cost $ 191,687 $ 145,070
Fair Value $ 308,226 $ 213,480
Preferred Equity | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 18.80% 17.00%
Preferred Equity | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 28.80% 23.20%
Common Equity/ Equivalents    
Summary of Investment Holdings [Line Items]    
Cost $ 49,597 $ 50,837
Fair Value $ 55,350 $ 93,465
Common Equity/ Equivalents | Investment Owned, at Cost | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 4.90% 6.00%
Common Equity/ Equivalents | Investment Owned, at Fair Value | Investment Type Concentration Risk    
Summary of Investment Holdings [Line Items]    
Percentage of Total Investments 5.20% 10.20%
[1] Cumulative gross unrealized appreciation for federal income tax purposes is $180.5 million; cumulative gross unrealized depreciation for federal income tax purposes is $115.8 million. Cumulative net unrealized appreciation is $64.7 million, based on a tax cost of $855.8 million.