Investments - Additional Information (Detail)	1 Months Ended
	Dec. 31, 2019 USD ($) Investment	Jan. 31, 2020 USD ($)	Nov. 30, 2019 USD ($)	Aug. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	82.70%				80.20%
Cost	$ 133,274,339				$ 76,774,339
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	17.50%				14.60%
Cost	$ 30,467,603				$ 15,000,000
Equity–55.1%
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	55.10%				50.40%
Cost	$ 85,106,736				$ 46,074,339
Senior secured debt - first lien
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	10.10%				15.20%
Cost	$ 17,700,000				$ 15,700,000
Total Senior Secured Notes
Schedule of Investments [Line Items]
Fair Value Percentage of Net Assets	27.60%				29.80%
Cost	$ 48,167,603				$ 30,700,000
Weighted Average Yield on Debt Investments	15.60%
Roundtables [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	81.00%
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				$ 2,000,000
Roundtables [Member] | Senior secured debt - second lien
Schedule of Investments [Line Items]
Cost	$ 12,100,000
Roundtables [Member] | Equity–55.1%
Schedule of Investments [Line Items]
Cost	32,400,000
Roundtables [Member] | Senior secured debt - first lien
Schedule of Investments [Line Items]
Cost	$ 2,000,000		$ 2,000,000
Lawn Doctor
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	62.00%				63.00%
Lawn Doctor | Senior secured debt - second lien
Schedule of Investments [Line Items]
Cost	$ 15,000,000
Lawn Doctor | Equity–55.1%
Schedule of Investments [Line Items]
Cost	$ 30,500,000
Polyform Products, Co.
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	87.00%				87.00%
Polyform Products, Co. | Equity–55.1%
Schedule of Investments [Line Items]
Cost	$ 15,600,000
Polyform Products, Co. | Senior secured debt - first lien
Schedule of Investments [Line Items]
Cost	$ 15,700,000
Milton [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	13.00%
Cost			$ 10,000,000
Milton [Member] | Senior secured debt - second lien
Schedule of Investments [Line Items]
Cost	$ 3,400,000
Milton [Member] | Equity–55.1%
Schedule of Investments [Line Items]
Cost	6,600,000
Resolution Economics
Schedule of Investments [Line Items]
Committed funding for co-investment with affiliate	$ 10,000,000
Resolution Economics | Subsequent Event [Member]
Schedule of Investments [Line Items]
Cost		$ 10,000,000
Resolution Economics | Subsequent Event [Member] | Equity–55.1%
Schedule of Investments [Line Items]
Cost		7,200,000
Resolution Economics | Subsequent Event [Member] | Total Senior Secured Notes
Schedule of Investments [Line Items]
Cost		$ 2,800,000