Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Realized gains or losses on investments	$ 0	$ 0
Net change in unrealized depreciation on investments	15,037,022	4,809,906
Level 3 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Net change in unrealized depreciation on investments	$ 15,037,022	$ 4,809,906