Quarterly report [Sections 13 or 15(d)]

Investments - Summary of Changes in Assets Measured at Fair Value Using Significant Unobservable Inputs (Details)

v3.25.3
Investments - Summary of Changes in Assets Measured at Fair Value Using Significant Unobservable Inputs (Details) - USD ($)
9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Change in unrealized appreciation/depreciation included in earnings related to Level 3 investments still held at reporting date $ (11,902,301) $ (776,811)
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Ending balance, of Level 3 Assets 70,818,041 69,816,062
Total realized (losses) gains, net (2,001,997) 6,148,837
Total unrealized (losses) gains (11,902,301) 3,332,234
Purchases of securities/changes to securities/non-cash conversions 5,203,762 12,430,020
Repayments and sales of securities (17,786,633) (16,691,586)
Ending balance, of Level 3 Assets 44,330,872 75,035,567
Change in unrealized appreciation/depreciation included in earnings related to Level 3 investments still held at reporting date (4,532,316) 1,460,229
Level 3 | Autotality (formerly Filterworks Acquisition USA, LLC)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 134,806  
Level 3 | BlackJet    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 2,501,187  
Level 3 | Swanson    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains   250,000
Purchases of securities/changes to securities/non-cash conversions 21,344  
Level 3 | FSS    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (3,829,281) (610,000)
Purchases of securities/changes to securities/non-cash conversions 1,053,470 107,619
Repayments and sales of securities   (34,838)
Level 3 | Caitec    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 448,972 434,064
Level 3 | Carolina Skiff    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (442,755)  
Purchases of securities/changes to securities/non-cash conversions 34,755  
Level 3 | FCM    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 484,837  
Purchases of securities/changes to securities/non-cash conversions 38,031 34,499
Level 3 | Filterworks    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains   (396,226)
Purchases of securities/changes to securities/non-cash conversions   193,885
Level 3 | GoNoodle    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (25)  
Purchases of securities/changes to securities/non-cash conversions 10,830 10,722
Level 3 | Hilton Displays    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions   16,069
Repayments and sales of securities (1,071,824)  
Level 3 | Highland    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 97,289 93,776
Level 3 | EFINEA    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 488,235  
Purchases of securities/changes to securities/non-cash conversions 17,177 33,995
Level 3 | ITA    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (875,000)  
Purchases of securities/changes to securities/non-cash conversions 375,000 771,009
Level 3 | DSD    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   23,699
Repayments and sales of securities   (23,699)
Level 3 | Knoa    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   (1,229,155)
Total unrealized (losses) gains   1,129,155
Level 3 | Mezmeriz    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   (742,850)
Total unrealized (losses) gains   742,850
Level 3 | Lumious    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (77,314)  
Repayments and sales of securities (712,630)  
Level 3 | Mattison    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions   5,572,902
Repayments and sales of securities (5,572,902) (1,894,470)
Level 3 | Microcision    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net 55,357  
Repayments and sales of securities (55,357)  
Level 3 | Mobile IV Nurses    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 125,000  
Purchases of securities/changes to securities/non-cash conversions 19,054  
Level 3 | MRES    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (739,352) (264,545)
Purchases of securities/changes to securities/non-cash conversions 359,419 3,213,545
Level 3 | Pressure Pro    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net 870,000  
Total unrealized (losses) gains (720,000) 720,000
Purchases of securities/changes to securities/non-cash conversions 22,445 52,129
Repayments and sales of securities (2,625,150) (1,427,452)
Level 3 | SciAps    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   7,699,879
Repayments and sales of securities   (1,291,386)
Level 3 | Seybert    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 256,000  
Purchases of securities/changes to securities/non-cash conversions 69,983 1,895,806
Repayments and sales of securities (7,748,770)  
Level 3 | Tilson    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (2,850,015) 397,264
Total unrealized (losses) gains (6,649,985) 1,761,000
Repayments and sales of securities   (397,264)
Level 3 | Loan investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Ending balance, of Level 3 Assets 15,037,873 12,417,977
Total realized (losses) gains, net (77,314)  
Total unrealized (losses) gains (875,000)  
Purchases of securities/changes to securities/non-cash conversions 720,710 6,777,975
Repayments and sales of securities (6,285,532) (1,894,470)
Transfers within Level 3 (4,799,278)  
Ending balance, of Level 3 Assets 3,721,459 17,301,482
Level 3 | Loan investments | Swanson    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 21,344  
Level 3 | Loan investments | Caitec    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 324,366 434,064
Level 3 | Loan investments | ITA    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (875,000)  
Purchases of securities/changes to securities/non-cash conversions 375,000 771,009
Level 3 | Loan investments | Lumious    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (77,314)  
Repayments and sales of securities (712,630)  
Level 3 | Loan investments | Mattison    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions   5,572,902
Repayments and sales of securities (5,572,902) (1,894,470)
Level 3 | Debt investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Ending balance, of Level 3 Assets 38,043,721 36,861,525
Total unrealized (losses) gains (3,586,177)  
Purchases of securities/changes to securities/non-cash conversions 4,198,297 5,279,881
Repayments and sales of securities (10,545,744) (3,552,290)
Transfers within Level 3 4,799,278  
Ending balance, of Level 3 Assets 32,909,375 38,589,116
Level 3 | Debt investments | Autotality (formerly Filterworks Acquisition USA, LLC)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 134,806  
Level 3 | Debt investments | BlackJet    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 2,251,187  
Level 3 | Debt investments | FSS    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (3,331,662)  
Purchases of securities/changes to securities/non-cash conversions 1,053,470  
Repayments and sales of securities   (34,838)
Level 3 | Debt investments | Caitec    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 124,606  
Level 3 | Debt investments | FCM    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 484,837  
Purchases of securities/changes to securities/non-cash conversions 38,031 34,499
Level 3 | Debt investments | Filterworks    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions   193,885
Level 3 | Debt investments | GoNoodle    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 10,830 10,722
Level 3 | Debt investments | Hilton Displays    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions   16,069
Repayments and sales of securities (1,071,824)  
Level 3 | Debt investments | Highland    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 97,289 93,776
Level 3 | Debt investments | EFINEA    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 17,177 33,995
Level 3 | Debt investments | Mobile IV Nurses    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 19,054  
Level 3 | Debt investments | MRES    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (739,352)  
Purchases of securities/changes to securities/non-cash conversions 359,419 2,949,000
Level 3 | Debt investments | Pressure Pro    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 22,445 52,129
Repayments and sales of securities (1,725,150) (1,427,452)
Level 3 | Debt investments | SciAps    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Repayments and sales of securities   (2,090,000)
Level 3 | Debt investments | Seybert    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 69,983 1,895,806
Repayments and sales of securities (7,748,770)  
Level 3 | Equity investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Ending balance, of Level 3 Assets 17,736,447 20,536,560
Total realized (losses) gains, net $ (1,924,683) 6,148,837
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Realized Investment Gains (Losses)  
Total unrealized (losses) gains $ (7,441,124) $ 3,332,234
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Change in unrealized appreciation/depreciation included in earnings related to Level 3 investments still held at reporting date Change in unrealized appreciation/depreciation included in earnings related to Level 3 investments still held at reporting date
Purchases of securities/changes to securities/non-cash conversions $ 284,755 $ 372,164
Repayments and sales of securities (955,357) (11,244,826)
Ending balance, of Level 3 Assets 7,700,038 19,144,969
Level 3 | Equity investments | BlackJet    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Purchases of securities/changes to securities/non-cash conversions 250,000  
Level 3 | Equity investments | Swanson    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains   250,000
Level 3 | Equity investments | FSS    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (497,619) (610,000)
Purchases of securities/changes to securities/non-cash conversions   107,619
Level 3 | Equity investments | Carolina Skiff    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains (442,755)  
Purchases of securities/changes to securities/non-cash conversions 34,755  
Level 3 | Equity investments | Filterworks    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains   (396,226)
Level 3 | Equity investments | GoNoodle    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (25)  
Level 3 | Equity investments | EFINEA    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 488,235  
Level 3 | Equity investments | DSD    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   23,699
Repayments and sales of securities   (23,699)
Level 3 | Equity investments | Knoa    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   (1,229,155)
Total unrealized (losses) gains   1,129,155
Level 3 | Equity investments | Mezmeriz    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   (742,850)
Total unrealized (losses) gains   742,850
Level 3 | Equity investments | Microcision    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net 55,357  
Repayments and sales of securities (55,357)  
Level 3 | Equity investments | Mobile IV Nurses    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 125,000  
Level 3 | Equity investments | MRES    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains   (264,545)
Purchases of securities/changes to securities/non-cash conversions   264,545
Level 3 | Equity investments | Pressure Pro    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net 870,000  
Total unrealized (losses) gains (720,000) 720,000
Repayments and sales of securities (900,000)  
Level 3 | Equity investments | SciAps    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net   7,699,879
Repayments and sales of securities   (10,823,863)
Level 3 | Equity investments | Seybert    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total unrealized (losses) gains 256,000  
Level 3 | Equity investments | Tilson    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total realized (losses) gains, net (2,850,015) 397,264
Total unrealized (losses) gains $ (6,649,985) 1,761,000
Repayments and sales of securities   $ (397,264)