Quarterly report pursuant to Section 13 or 15(d)

INVESTMENTS - Narrative (Details)

v3.25.0.1
INVESTMENTS - Narrative (Details)
$ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended
Dec. 31, 2024
USD ($)
state
portfolioCompany
industry
Nov. 30, 2024
USD ($)
Sep. 30, 2024
USD ($)
Jul. 31, 2024
USD ($)
May 31, 2024
USD ($)
Dec. 31, 2024
USD ($)
state
portfolioCompany
industry
Dec. 31, 2023
USD ($)
Dec. 31, 2024
USD ($)
state
portfolioCompany
industry
Dec. 31, 2023
USD ($)
Mar. 31, 2024
USD ($)
Summary of Investment Holdings [Line Items]                    
Principal repayments of investments               $ 33,500 $ 27,500  
Purchase of investments               207,192 182,988  
Success fee income           $ 843 $ 1,382 $ 2,546 $ 1,382  
Number of investment portfolio company | portfolioCompany 26         26   26    
Number of states or countries which have invested in the company location | state 20         20   20    
Number of industries that have made investments | industry 17         17   17    
Fair Value $ 1,072,230         $ 1,072,230   $ 1,072,230   $ 920,504 [1]
Uncollectible receivables allowance, minimum required day for uncollectible adjustment               90 days    
Gross receivables from portfolio companies 2,400         2,400   $ 2,400   2,200
Allowance for uncollectible receivables 1,600         1,600   1,600   1,400
Secured First Lien Debt                    
Summary of Investment Holdings [Line Items]                    
Fair Value 599,911         599,911   599,911   474,856
Preferred Equity                    
Summary of Investment Holdings [Line Items]                    
Fair Value 308,226         308,226   308,226   $ 213,480
Five Largest Portfolio Investments | Investment Portfolio Benchmark | Customer Concentration Risk                    
Summary of Investment Holdings [Line Items]                    
Fair Value 443,500         $ 443,500   $ 443,500    
Percentage of Total Investments               41.40%    
Funko Acquisition Holdings, LLC                    
Summary of Investment Holdings [Line Items]                    
Principal repayments of investments         $ 21          
Realized gain on preferred equity         $ 2          
Nocturne Villa Rentals, Inc.                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments       $ 18,500            
Nth Degree Investment Group, LLC                    
Summary of Investment Holdings [Line Items]                    
Principal repayments of investments     $ 25,000              
Realized gain on preferred equity     42,300              
Success fee income     $ 100              
Pyrotek Special Effects, Inc. ("Pyrotek")                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments   $ 27,200                
Pyrotek Special Effects, Inc. ("Pyrotek") | Secured First Lien Debt                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments   20,100                
Pyrotek Special Effects, Inc. ("Pyrotek") | Preferred Equity                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments   $ 7,100                
Gladstone Alternative Income Fund ("GALT")                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 5,000                  
Nielsen-Kellerman, Inc. ("Nielsen-Kellerman")                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 71,300                  
Nielsen-Kellerman, Inc. ("Nielsen-Kellerman") | Secured First Lien Debt                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 49,100                  
Nielsen-Kellerman, Inc. ("Nielsen-Kellerman") | Preferred Equity                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 22,200                  
Ricardo Defense, Inc. ("Ricardo")                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 78,700                  
Ricardo Defense, Inc. ("Ricardo") | Secured First Lien Debt                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments 61,300                  
Ricardo Defense, Inc. ("Ricardo") | Preferred Equity                    
Summary of Investment Holdings [Line Items]                    
Purchase of investments $ 17,400                  
[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.