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Nature of Organization and Operations - Additional Information (Detail) - USD ($)			12 Months Ended
	Jul. 02, 2018	Jun. 28, 2018	Dec. 31, 2018	Dec. 31, 2019
Class Of Stock [Line Items]
Underwriting discounts and commissions and offering expenses paid			$ 3,502,543
Proceeds from sale of common stock			51,621,570
Cash and cash equivalents			$ 62,614,010	$ 38,524,536
2018 Public Offering [Member]
Class Of Stock [Line Items]
Common stock sold in offering		11,688,000
Underwriting discounts and commissions and offering expenses paid	$ 3,500,000
Proceeds from sale of common stock	$ 48,100,000
Underwriters' Exercise of Option [Member]
Class Of Stock [Line Items]
Common stock sold in offering	1,720,200