Annual report pursuant to Section 13 and 15(d)

INVESTMENTS - Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details)

v3.24.1.u1
INVESTMENTS - Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Mar. 31, 2024
Mar. 31, 2023
Oct. 31, 2023
Sep. 30, 2022
Aug. 31, 2022
Mar. 31, 2022
Aug. 31, 2012
New investments, repayments and settlements:              
Cost $ 854,290 [1] $ 720,630 [2]          
Fair value 920,504 [1] 753,543 [2]          
Horizon Facilities Services, Inc.              
New investments, repayments and settlements:              
Realized gain (loss) on preferred equity   12,300          
SFEG Holdings, Inc              
New investments, repayments and settlements:              
Cost     $ 4,800        
Fair value     $ 8,600        
Ginsey Home Solutions, Inc.              
New investments, repayments and settlements:              
Cost         $ 12,200   $ 5,000
Fair value         $ 12,200    
PSI Molded Plastics, Inc              
New investments, repayments and settlements:              
Cost       $ 26,600      
Fair value       $ 26,600      
Total              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Beginning balance 920,486 753,516       $ 714,322  
New investments, repayments and settlements:              
Issuances / originations 183,924 133,768          
Settlements / repayments (28,000) (57,396)          
Sales (52,228) (35,758)          
Transfers 0 0          
Ending balance 920,486 753,516          
Total | Debt and Equity Securities, Realized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 29,964 10,778          
Total | Debt and Equity Securities, Unrealized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 62,319 (9,949)          
Reversal of previously recorded (appreciation) depreciation upon realization (29,009) (2,249)          
Secured First Lien Debt              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Beginning balance 474,856 437,517       425,087  
New investments, repayments and settlements:              
Issuances / originations 74,536 107,200          
Settlements / repayments (28,000) (50,800)          
Sales 0 0          
Transfers 0 (14,418)          
Ending balance 474,856 437,517          
Secured First Lien Debt | Debt and Equity Securities, Realized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) (4,550) 0          
Secured First Lien Debt | Debt and Equity Securities, Unrealized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) (7,859) (29,552)          
Reversal of previously recorded (appreciation) depreciation upon realization 3,212 0          
Secured Second Lien Debt              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Beginning balance 138,703 75,734       67,958  
New investments, repayments and settlements:              
Issuances / originations 64,000 5,188          
Settlements / repayments 0 (6,596)          
Sales 0 0          
Transfers 0 14,418          
Ending balance 138,703 75,734          
Secured Second Lien Debt | Debt and Equity Securities, Realized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) (3,200) (10,000)          
Secured Second Lien Debt | Debt and Equity Securities, Unrealized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) (1,031) (5,235)          
Reversal of previously recorded (appreciation) depreciation upon realization 3,200 10,001          
Preferred Equity              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Beginning balance 213,480 222,585       217,599  
New investments, repayments and settlements:              
Issuances / originations 14,688 21,000          
Settlements / repayments 0 0          
Sales (50,726) (35,758)          
Transfers (8,621) 0          
Ending balance 213,480 222,585          
Preferred Equity | Debt and Equity Securities, Realized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 36,833 20,778          
Preferred Equity | Debt and Equity Securities, Unrealized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 34,050 11,216          
Reversal of previously recorded (appreciation) depreciation upon realization (35,329) (12,250)          
Common Equity/ Equivalents              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Beginning balance 93,447 17,680       $ 3,678  
New investments, repayments and settlements:              
Issuances / originations 30,700 380          
Settlements / repayments 0 0          
Sales (1,502) 0          
Transfers 8,621 0          
Ending balance 93,447 17,680          
Common Equity/ Equivalents | Debt and Equity Securities, Realized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 881 0          
Common Equity/ Equivalents | Debt and Equity Securities, Unrealized Gain (Loss)              
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]              
Total gain (loss) 37,159 13,622          
Reversal of previously recorded (appreciation) depreciation upon realization $ (92) $ 0          
[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.
[2] Cumulative gross unrealized appreciation for federal income tax purposes is $150.4 million; cumulative gross unrealized depreciation for federal income tax purposes is $119.3 million. Cumulative net unrealized appreciation is $31.1 million, based on a tax cost of $722.4 million.