Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Net change in unrealized (depreciation) appreciation on investments	$ (3,393,662)	$ 281,000
Investments, at fair value	$ 163,301,338		$ 144,195,000

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Balance Type:	debit
Period Type:	instant