Investments - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020 USD ($) Investment	Dec. 31, 2019 USD ($)
Schedule of Investments [Line Items]
Purchases of Investments Net	$ 22,500,000
Fair Value Percentage of Net Assets	83.90%	82.70%
Cost	$ 155,774,339	$ 133,274,339
Number of debt investments on non accrual status | Investment	0
Senior secured debt - second lien
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	18.50%	17.50%
Cost	$ 35,942,454	$ 30,467,603
Equity–56.3%
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	56.30%	55.10%
Cost	$ 102,131,885	$ 85,106,736
Senior secured debt - first lien
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	9.10%	10.10%
Cost	$ 17,700,000	$ 17,700,000
Total Senior Secured Notes
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	27.60%	27.60%
Cost	$ 53,642,454	$ 48,167,603
Weighted Average Yield on Debt Investments	15.50%
Roundtables [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	81.00%
Lawn Doctor, Inc.
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	62.00%
Polyform Products, Co.
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	87.00%