| Summary of the Significant Unobservable Inputs to Determine the Fair Value of Level 3 Portfolio Investments | The following table provides a summary of the significant unobservable inputs used to determine the fair value of the Corporation’s Level 3 portfolio investments as of September 30, 2023:   
        
         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
         | 
 Investment Type
 |   | Market Approach EBITDA Multiple |   |   | Market Approach Liquidation Seniority |   |   | Market ApproachRevenue Multiple
 |   |   | Market Approach Transaction Pricing |   |   | Totals |   |  
         | Non-Control/Non-Affiliate Equity |   | $ | 300,000 |   |   | $ | — |   |   | $ | 700,000 |   |   | $ | 200,063 |   |   | $ | 1,200,063 |   |  
         | Non-Control/Non-Affiliate Loan and Debt |   |   | 6,641,504 |   |   |   | 2,212,326 |   |   |   | — |   |   |   | 2,250,000 |   |   |   | 11,103,830 |   |  
         | Total Non-Control/Non-Affiliate |   | $ | 6,941,504 |   |   | $ | 2,212,326 |   |   | $ | 700,000 |   |   | $ | 2,450,063 |   |   | $ | 12,303,893 |   |  
         | Affiliate Equity |   | $ | 4,262,324 |   |   | $ | — |   |   | $ | 3,223,984 |   |   | $ | 11,550,000 |   |   | $ | 19,036,308 |   |  
         | Affiliate Loan and Debt |   |   | 18,357,414 |   |   |   | — |   |   |   | 2,090,000 |   |   |   | 11,613,593 |   |   |   | 32,061,007 |   |  
         | Total Affiliate |   | $ | 22,619,738 |   |   | $ | — |   |   | $ | 5,313,984 |   |   | $ | 23,163,593 |   |   | $ | 51,097,315 |   |  
         | Control Equity |   | $ | — |   |   | $ | — |   |   | $ | — |   |   | $ | — |   |   | $ | — |   |  
         | Control Loan and Debt |   |   | — |   |   |   | 4,083,489 |   |   |   | — |   |   |   | — |   |   |   | 4,083,489 |   |  
         | Total Control |   | $ | — |   |   | $ | 4,083,489 |   |   | $ | — |   |   | $ | — |   |   | $ | 4,083,489 |   |  
         | Total Level 3 Investments |   | $ | 29,561,242 |   |   | $ | 6,295,815 |   |   | $ | 6,013,984 |   |   | $ | 25,613,656 |   |   | $ | 67,484,697 |   |  
         |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Range |   | 4X - 7X |   |   | 1X |   |   | 1X - 3X |   |   | Not Applicable |   |   |   |   |  
         | Unobservable Input |   | EBITDA Multiple |   |   | Asset Value |   |   | Revenue Multiple |   |   | Transaction Price |   |   |   |   |  
         | Weighted Average |   | 5.4X |   |   | 1X |   |   | 1.7X |   |   | Not Applicable |   |   |   |   |  | 
| summary of the components of Assets Measured at Fair Value | The following table provides a summary of the components of Level 1, 2 and 3 Assets Measured at Fair Value at September 30, 2023:   
        
         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
         |   |   |   |   |   | Fair Value Measurements at Reported Date Using |   |  
         | 
 
 Description
 |   | September 30, 2023 |   |   | Quoted Prices in Active Markets for Identical Assets(Level 1)
 |   |   | SignificantObservable Inputs
 (Level 2)
 |   |   | Other SignificantUnobservable
 Inputs
 (Level 3)
 |   |  
         | Loan investments |   | $ | 12,170,088 |   |   | $ | — |   |   | $ | — |   |   | $ | 12,170,088 |   |  
         | Debt investments |   |   | 35,078,238 |   |   |   | — |   |   |   | — |   |   |   | 35,078,238 |   |  
         | Equity investments |   |   | 27,435,959 |   |   |   | 7,199,588 |   |   |   | — |   |   |   | 20,236,371 |   |  
         | Total |   | $ | 74,684,285 |   |   | $ | 7,199,588 |   |   | $ | — |   |   | $ | 67,484,697 |   |    The following table provides a summary of the components of Level 1, 2 and 3 Assets Measured at Fair Value at December 31, 2022:   
        
         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
         |   |   |   |   |   | Fair Value Measurements at Reported Date Using |   |  
         | 
 
 Description
 |   | December 31, 2022 |   |   | Quoted Prices in Active Markets for Identical Assets(Level 1)
 |   |   | SignificantObservable Inputs
 (Level 2)
 |   |   | Other SignificantUnobservable
 Inputs
 (Level 3)
 |   |  
         | Loan investments |   | $ | 14,578,351 |   |   | $ | — |   |   | $ | — |   |   | $ | 14,578,351 |   |  
         | Debt investments |   |   | 19,582,616 |   |   |   | — |   |   |   | — |   |   |   | 19,582,616 |   |  
         | Equity investments |   |   | 27,343,292 |   |   |   | 6,407,548 |   |   |   | — |   |   |   | 20,935,744 |   |  
         | Total |   | $ | 61,504,259 |   |   | $ | 6,407,548 |   |   | $ | — |   |   | $ | 55,096,711 |   |  | 
| Summary of changes in Assets Measured at Fair Value Using Significant Unobservable Inputs (Level 3) | The following table provides a summary of changes in Assets Measured at Fair Value Using Significant Unobservable Inputs (Level 3) for the nine months ended September 30, 2023: 
        
         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
         |   |   | Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
 |   |  
         | Description |   | Loan Investments |   |   | DebtInvestments
 |   |   | EquityInvestments
 |   |   | Total |   |  
         | Ending balance December 31, 2022, of Level 3 Assets |   | $ | 14,578,351 |   |   | $ | 19,582,616 |   |   | $ | 20,935,744 |   |   | $ | 55,096,711 |   |  
         | Realized gains (losses) included in net change in net assets fromoperations:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | ClearView Social, Inc. (Clearview Social) |   |   | — |   |   |   | — |   |   |   | 10,432 |   |   |   | 10,432 |   |  
         | DSD Operating, LLC (DSD) |   |   | — |   |   |   | — |   |   |   | 2,537,765 |   |   |   | 2,537,765 |   |  
         | Microcision, LLC (Microcision) |   |   | — |   |   |   | — |   |   |   | 58,329 |   |   |   | 58,329 |   |  
         | Rheonix, Inc. (Rheonix) |   |   | — |   |   |   | — |   |   |   | (2,802,731 | ) |   |   | (2,802,731 | ) |  
         | SocialFlow, Inc. (Social Flow) |   |   | — |   |   |   | — |   |   |   | (4,941 | ) |   |   | (4,941 | ) |  
         | Somerset Gas Transmission Company, LLC (Somerset) |   |   | — |   |   |   | — |   |   |   | (448,717 | ) |   |   | (448,717 | ) |  
         | Total realized losses, net |   |   | — |   |   |   | — |   |   |   | (649,863 | ) |   |   | (649,863 | ) |  
         | Unrealized gains (losses) included in net change in net assetsfrom operations:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | DSD |   |   | — |   |   |   | — |   |   |   | (886,698 | ) |   |   | (886,698 | ) |  
         | Open Exchange, Inc. (Open Exchange) |   |   | — |   |   |   | — |   |   |   | (701,940 | ) |   |   | (701,940 | ) |  
         | Rheonix |   |   | — |   |   |   | — |   |   |   | 2,802,731 |   |   |   | 2,802,731 |   |  
         | Somerset |   |   | — |   |   |   | — |   |   |   | 594,097 |   |   |   | 594,097 |   |  
         | Total unrealized gains (losses) |   |   | — |   |   |   | — |   |   |   | 1,808,190 |   |   |   | 1,808,190 |   |  
         | Purchases of securities/changes to securities/non-cashconversions:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | BMP Food Service Supply Holdco, LLC (FSS) |   |   | — |   |   |   | 2,320,000 |   |   |   | — |   |   |   | 2,320,000 |   |  
         | BMP Swanson Holdco, LLC (Swanson) |   |   | 100,115 |   |   |   | — |   |   |   | — |   |   |   | 100,115 |   |  
         | Caitec, Inc. (Caitec) |   |   | 55,822 |   |   |   | — |   |   |   | — |   |   |   | 55,822 |   |  
         | DSD |   |   | 31,652 |   |   |   | — |   |   |   | — |   |   |   | 31,652 |   |  
         | FCM Industries Holdco LLC (First Coast Mulch) |   |   | — |   |   |   | 3,807,147 |   |   |   | — |   |   |   | 3,807,147 |   |  
         | Filterworks Acquisition USA, LLC (Filterworks) |   |   | — |   |   |   | 204,489 |   |   |   | — |   |   |   | 204,489 |   |  
         | GoNoodle, Inc. (GoNoodle) |   |   | — |   |   |   | 10,614 |   |   |   | — |   |   |   | 10,614 |   |  
         | HDI Acquisition LLC (Hilton Displays) |   |   | — |   |   |   | 17,182 |   |   |   | — |   |   |   | 17,182 |   |  
         | Highland All About People Holdings, Inc. (All About People) |   |   | — |   |   |   | 3,018,000 |   |   |   | 1,000,000 |   |   |   | 4,018,000 |   |  
         | Inter-National Electronic Alloys LLC (INEA) |   |   | — |   |   |   | 3,321,071 |   |   |   | 1,011,765 |   |   |   | 4,332,836 |   |  
         | ITA Acquisition, LLC (ITA) |   |   | 547,282 |   |   |   | — |   |   |   | — |   |   |   | 547,282 |   |  
         | Mattison Avenue Holdings LLC (Mattison) |   |   | 28,300 |   |   |   | — |   |   |   | — |   |   |   | 28,300 |   |  
         | Pressure Pro, Inc. (Pressure Pro) |   |   | — |   |   |   | 3,038,446 |   |   |   | 30,000 |   |   |   | 3,068,446 |   |  
         | Seybert’s Billiards Corporation (Seybert’s) |   |   | — |   |   |   | 93,720 |   |   |   | — |   |   |   | 93,720 |   |  
         | SciAps, Inc. (Sciaps) |   |   | — |   |   |   | 5,000 |   |   |   | — |   |   |   | 5,000 |   |  
         | Social Flow |   |   | — |   |   |   | — |   |   |   | 4,941 |   |   |   | 4,941 |   |  
         | Tilson Technology Management, Inc. (Tilson) |   |   | — |   |   |   | — |   |   |   | 250,000 |   |   |   | 250,000 |   |  
         | Total purchases of securities/changes to securities/non-cashconversions
 |   |   | 763,171 |   |   |   | 15,835,669 |   |   |   | 2,296,706 |   |   |   | 18,895,546 |   |  
         | Repayments and sales of securities: |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Clearview Social |   |   | — |   |   |   | — |   |   |   | (10,432 | ) |   |   | (10,432 | ) |  
         | DSD |   |   | (3,171,434 | ) |   |   | — |   |   |   | (3,605,265 | ) |   |   | (6,776,699 | ) |  
         | FSS |   |   | — |   |   |   | (40,047 | ) |   |   | (210,000 | ) |   |   | (250,047 | ) |  
         | Hilton Displays |   |   | — |   |   |   | (300,000 | ) |   |   | — |   |   |   | (300,000 | ) |  
         | Microcision |   |   | — |   |   |   | — |   |   |   | (58,329 | ) |   |   | (58,329 | ) |  
         | Somerset |   |   | — |   |   |   | — |   |   |   | (270,380 | ) |   |   | (270,380 | ) |  
         | Total repayments and sales of securities |   |   | (3,171,434 | ) |   |   | (340,047 | ) |   |   | (4,154,406 | ) |   |   | (7,665,887 | ) |  
         | Ending balance September 30, 2023, of Level 3 Assets |   | $ | 12,170,088 |   |   | $ | 35,078,238 |   |   | $ | 20,236,371 |   |   | $ | 67,484,697 |   |  
         |   |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Change in unrealized appreciation/depreciation included in earningsrelated to Level 3 investments still held at reporting date
 |   |   |   |   |   |   |   |   |   |   | $ | (701,940 | ) |    The following table provides a summary of changes in Assets Measured at Fair Value Using Significant Unobservable Inputs (Level 3) for the nine months ended September 30, 2022:   
        
         |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
         |   |   | Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
 |   |  
         | Description
 |   | Loan Investments |   |   | DebtInvestments
 |   |   | EquityInvestments
 |   |   | Total |   |  
         | Ending Balance December 31, 2021, of Level 3 Assets |   | $ | 15,503,404 |   |   | $ | 14,030,078 |   |   | $ | 20,633,935 |   |   | $ | 50,167,417 |   |  
         | Realized gains (losses) included in net change in net assetsfrom operations:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | ClearView Social, Inc. (Clearview Social) |   |   | — |   |   |   | — |   |   |   | 38,881 |   |   |   | 38,881 |   |  
         | GiveGab, Inc. (Givegab) |   |   | — |   |   |   | — |   |   |   | 1,919 |   |   |   | 1,919 |   |  
         | Microcision, LLC (Microcision) |   |   | — |   |   |   | — |   |   |   | 190,000 |   |   |   | 190,000 |   |  
         | New Monarch Machine Tool, Inc. (New Monarch) |   |   | — |   |   |   | — |   |   |   | (22,841 | ) |   |   | (22,841 | ) |  
         | SocialFlow, Inc. (Social Flow) |   |   | — |   |   |   | — |   |   |   | (1,481,498 | ) |   |   | (1,481,498 | ) |  
         | Total realized (losses), net |   |   | — |   |   |   | — |   |   |   | (1,273,539 | ) |   |   | (1,273,539 | ) |  
         | Unrealized gains included in net change in net assets from operations:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Microcision |   |   | — |   |   |   | — |   |   |   | 25,000 |   |   |   | 25,000 |   |  
         | New Monarch |   |   | — |   |   |   | — |   |   |   | 22,841 |   |   |   | 22,841 |   |  
         | Social Flow |   |   | — |   |   |   | — |   |   |   | 1,628,000 |   |   |   | 1,628,000 |   |  
         | Total unrealized gains |   |   | — |   |   |   | — |   |   |   | 1,675,841 |   |   |   | 1,675,841 |   |  
         | Purchases of securities/changes to securities/non-cashconversions:
 |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Caitec, Inc. (Caitec) |   |   | 54,704 |   |   |   | — |   |   |   | — |   |   |   | 54,704 |   |  
         | DSD Operating, LLC (DSD) |   |   | 364,633 |   |   |   | — |   |   |   | — |   |   |   | 364,633 |   |  
         | Filterworks Acquisition USA, LLC (Filterworks) |   |   | — |   |   |   | 146,723 |   |   |   | 86,213 |   |   |   | 232,936 |   |  
         | GoNoodle, Inc. (GoNoodle) |   |   | — |   |   |   | 10,622 |   |   |   | — |   |   |   | 10,622 |   |  
         | HDI Acquisition LLC (Hilton Displays) |   |   | — |   |   |   | 19,835 |   |   |   | — |   |   |   | 19,835 |   |  
         | ITA Acquisition, LLC (ITA) |   |   | 52,475 |   |   |   | — |   |   |   | 623,810 |   |   |   | 676,285 |   |  
         | Mattison Avenue Holdings LLC (Mattison) |   |   | 27,734 |   |   |   | — |   |   |   | — |   |   |   | 27,734 |   |  
         | Seybert’s Billiards Corporation (Seybert’s) |   |   | — |   |   |   | 2,279,234 |   |   |   | — |   |   |   | 2,279,234 |   |  
         | SciAps, Inc. (Sciaps) |   |   | — |   |   |   | 11,250 |   |   |   | — |   |   |   | 11,250 |   |  
         | Total purchases of securities/changes to securities/non-cashconversions
 |   |   | 499,546 |   |   |   | 2,467,664 |   |   |   | 710,023 |   |   |   | 3,677,233 |   |  
         | Repayments and sale of securities: |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Clearview Social |   |   | — |   |   |   | — |   |   |   | (38,881 | ) |   |   | (38,881 | ) |  
         | Givegab |   |   | — |   |   |   | — |   |   |   | (1,919 | ) |   |   | (1,919 | ) |  
         | GoNoodle |   |   | — |   |   |   | (90,175 | ) |   |   | — |   |   |   | (90,175 | ) |  
         | Microcision |   |   | — |   |   |   | — |   |   |   | (300,000 | ) |   |   | (300,000 | ) |  
         | Social Flow |   |   | — |   |   |   | — |   |   |   | (268,502 | ) |   |   | (268,502 | ) |  
         | Total repayments and sale of securities |   |   | — |   |   |   | (90,175 | ) |   |   | (609,302 | ) |   |   | (699,477 | ) |  
         | Ending Balance September 30, 2022, of Level 3 Assets |   | $ | 16,002,950 |   |   | $ | 16,407,567 |   |   | $ | 21,136,958 |   |   | $ | 53,547,475 |   |  
         |   |   |   |   |   |   |   |   |   |   |   |   |   |  
         | Change in unrealized appreciation/depreciation included in earningsrelated to Level 3 investments still held at reporting date
 |   |   |   |   |   |   |   |   |   |   | $ | — |   |  |