Convertible Preferred Stock - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Aug. 31, 2017	Dec. 31, 2018	Dec. 31, 2019
Class Of Stock [Line Items]
Authorized capital stock		10,000,000	10,000,000
Convertible preferred stock issued and sold		0	0
Stock issuance costs		$ 18,180
Series E Convertible Preferred Stock [Member]
Class Of Stock [Line Items]
Convertible preferred stock issued and sold	7,792,035
Preferred stock, par value	$ 2.571
Gross proceeds from issuance and sale of convertible preferred stock	$ 20,033,322
Stock issuance costs	$ 285,475