v3.25.2
Transactions with Controlled Companies - R-V Industries, Inc. (Details) - USD ($)
$ in Thousands
 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2023
Dec. 15, 2020
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Interest Income $ 671,109 $ 770,312 $ 760,785  
Dividend Income 19,378 11,953 8,405  
Advisory Fee 12,348 27,666 18,131  
Total Other Income 28,949 79,397 83,023  
Interest Receivable $ 25,144 26,936    
Senior Subordinated Notes        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Restructured debt       $ 28,622
First Lien Note        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Principal amount       $ 28,622
R-V Industries, Inc. | Members of R-V Industries Management        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Ownership interest 12.25%      
Reportable Legal Entities | Subsidiaries | R-V Industries, Inc.        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Interest Income $ 5,558 5,358 4,467  
Dividend Income 8,774 0 0  
Advisory Fee 0 106 158  
Total Other Income 0 106 158  
Additions 10,000 3,700 0  
Interest Receivable 16 45    
Other Receivables 8 0    
Reportable Legal Entities | Subsidiaries | R-V Industries, Inc. | Prospect Administration        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Managerial Assistance 180 180 180  
Reimbursement of Legal, Tax, etc $ 14 $ 17 $ 18  
Reportable Legal Entities | Subsidiaries | R-V Industries, Inc.        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Ownership interest 87.75%