v3.26.1
Borrowings - Narrative (Details)
1 Months Ended 3 Months Ended 6 Months Ended
Mar. 02, 2026
USD ($)
Feb. 27, 2026
USD ($)
Nov. 25, 2025
Feb. 12, 2025
USD ($)
Feb. 28, 2022
USD ($)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Sep. 30, 2025
Aug. 06, 2024
USD ($)
Aug. 05, 2024
USD ($)
Mar. 01, 2021
USD ($)
Mar. 19, 2020
USD ($)
Feb. 28, 2014
USD ($)
Debt Instrument [Line Items]                                    
Total Commitment               $ 550,000,000   $ 550,000,000   $ 675,000,000            
Outstanding borrowings under credit facility               195,000,000   195,000,000   95,000,000            
Deferred credit facility costs               3,981,000   3,981,000   4,643,000            
Credit facility, average outstanding borrowings               $ 200,800,000 $ 29,700,000 $ 166,400,000 $ 17,400,000              
Credit facility, average interest rate (in percentage)               7.02% 8.30% 7.06% 8.30%              
Assets               $ 809,044,000   $ 809,044,000   839,649,000            
Debt fair value               445,800,000   445,800,000   472,813,000            
Asset Pledged as Collateral                                    
Debt Instrument [Line Items]                                    
Assets               420,100,000   420,100,000   427,200,000            
Asset Not Pledged as Collateral                                    
Debt Instrument [Line Items]                                    
Assets               388,900,000   $ 388,900,000   412,500,000            
Unsecured Debt | 2025 Notes                                    
Debt Instrument [Line Items]                                    
Face amount                                 $ 70,000,000.0  
Stated interest rate                                 4.50%  
Repayments of debt             $ 70,000,000.0                      
Asset coverage ratio, minimum                   1.50                
Interest coverage ratio, minimum                   1.25                
Minimum stockholders' equity balance               216,100,000   $ 216,100,000                
Upward adjustment, issuance proceeds (in percentage)                   65.00%                
Unsecured Debt | 2026 Notes                                    
Debt Instrument [Line Items]                                    
Total Commitment               0   $ 0   200,000,000            
Face amount                               $ 200,000,000.0    
Stated interest rate                               4.50%    
Repayments of debt           $ 200,000,000.0                        
Debt fair value               0.0   0.0   202,100,000            
Unsecured Debt | 2027 Notes                                    
Debt Instrument [Line Items]                                    
Total Commitment               125,000,000   125,000,000   125,000,000            
Face amount         $ 125,000,000.0                          
Stated interest rate         5.00%                          
Debt term         5 years                          
Debt fair value               124,900,000   124,900,000   124,200,000            
Aggregate principal balance, secured status threshold         $ 25,000,000                          
Interest rate, below investment grade event         6.00%                          
Unsecured Debt | 8.11% 2028 Notes                                    
Debt Instrument [Line Items]                                    
Total Commitment               $ 50,000,000   $ 50,000,000   50,000,000            
Face amount       $ 50,000,000.0                            
Stated interest rate       8.11%       8.11%   8.11%     9.11%          
Asset coverage ratio, minimum       1.50                            
Interest coverage ratio, minimum       1.25                            
Minimum stockholders' equity balance       $ 236,776,000                            
Upward adjustment, issuance proceeds (in percentage)       65.00%                            
Debt term                   3 years                
Debt fair value               $ 51,700,000   $ 51,700,000   52,500,000            
Aggregate principal balance, secured status threshold       $ 25,000,000                            
Interest rate, below investment grade event       1.00%                            
Ratio calculation period       6 months                            
Unsecured Debt | 7.50% 2028 Notes                                    
Debt Instrument [Line Items]                                    
Total Commitment               75,000,000   75,000,000   0            
Deferred credit facility costs               $ 200,000   $ 200,000                
Face amount   $ 75,000,000.0                                
Stated interest rate   7.50%           7.50%   7.50%                
Repayments of debt $ 200,000,000.0                                  
Asset coverage ratio, minimum   1.50                                
Minimum stockholders' equity balance   $ 230,800,000                                
Upward adjustment, issuance proceeds (in percentage)   25.00%                                
Debt term                   3 years                
Debt fair value               $ 75,100,000   $ 75,100,000                
Interest rate, below investment grade event   1.00%                                
Downward adjustment, issuance proceeds (in percentage)   25.00%                                
Interest rate, secured debt ratio event   1.50%                                
Interest rate, below investment grade and secured debt ratio event   2.00%                                
Payment in Kind (PIK) Note | 8.11% 2028 Notes                                    
Debt Instrument [Line Items]                                    
Ratio calculation period       6 months                            
Paid in kind interest to total interest       35.00%                            
Revolving Credit Facility | Line of Credit                                    
Debt Instrument [Line Items]                                    
Total Commitment               300,000,000   $ 300,000,000   300,000,000   $ 300,000,000 $ 350,000,000     $ 150,000,000.0
Debt instrument, variable interest rate, type flag     Secured Overnight Financing Rate (SOFR) [Member]             Secured Overnight Financing Rate (SOFR) [Member]                
Floor interest rate     0.50%             0.50%                
Current borrowing capacity               300,000,000   $ 300,000,000                
Accordion feature, higher borrowing capacity option               400,000,000   $ 400,000,000                
Unused commitment fee (in percentage)                   0.50%                
Outstanding borrowings under credit facility               195,000,000.0   $ 195,000,000.0   95,000,000.0            
Deferred credit facility costs               4,000,000.0   4,000,000.0   4,600,000            
Debt fair value               $ 195,000,000   $ 195,000,000   $ 95,000,000            
Revolving Credit Facility | Line of Credit | Maximum                                    
Debt Instrument [Line Items]                                    
Advance rate                   55.00%                
Revolving Credit Facility | Line of Credit | Greater than or equal to 75%                                    
Debt Instrument [Line Items]                                    
Basis spread on variable rate     2.75%             2.75%                
Facility utilization (in percentage)     75.00%             75.00%                
Revolving Credit Facility | Line of Credit | Greater than or equal to 50%                                    
Debt Instrument [Line Items]                                    
Basis spread on variable rate     2.85%             2.85%                
Revolving Credit Facility | Line of Credit | Greater than or equal to 50% | Minimum                                    
Debt Instrument [Line Items]                                    
Facility utilization (in percentage)     50.00%             50.00%                
Revolving Credit Facility | Line of Credit | Greater than or equal to 50% | Maximum                                    
Debt Instrument [Line Items]                                    
Facility utilization (in percentage)     75.00%             75.00%                
Revolving Credit Facility | Line of Credit | Less than 50%                                    
Debt Instrument [Line Items]                                    
Basis spread on variable rate     3.00%             3.00%                
Facility utilization (in percentage)     50.00%             50.00%                
Revolving Credit Facility | Line of Credit | During amortization period                                    
Debt Instrument [Line Items]                                    
Basis spread on variable rate     4.50%             4.50%