Common Stock - Additional Information (Detail) - USD ($)					9 Months Ended
	Sep. 30, 2020	Jul. 16, 2020	Jun. 01, 2020	Mar. 27, 2020	Sep. 30, 2020	Dec. 31, 2019
Changes In Equity And Comprehensive Income Line Items [Line Items]
Proceeds from issuance of common stock in public offering, net					$ 25,614,836
Common stock par value	$ 0.0001				$ 0.0001	$ 0.0001
Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights	0				0
Public Offering [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Gross proceeds from offering including exercise of underwriter's option		$ 132,200,000
Public Offering [Member] | Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights		1,630,436
Exercise price of warrants or rights		$ 0.0001
Purchase price of warrants issued		$ 22.9999
Ownership percentage on exercise of warrants without notice, minimum		4.99%
Ownership percentage on exercise of warrants with notice, maximum		19.99%
Notice period to increase ownership percentage on exercise of warrants		61 days
Public Offering [Member] | Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold		3,369,564
Public offering price, per share		$ 23.00
Over-Allotment Option [Member] | Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold		750,000
Proceeds from issuance of common stock in public offering, net		$ 124,000,000
At-The-Market Offering [Member] | Equity Distribution Agreement [Member] | JMP Securities LLC [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Shares of common stock sold	3,213,009
Proceeds from issuance of common stock in public offering, net	$ 25,600,000
Common stock par value				$ 0.0001
Aggregate offering price			$ 50,000,000	$ 18,900,000
Common stock available to be sold	23,400,000				$ 23,400,000
Issuance costs	300,000
Deferred offering costs	$ 200,000				$ 200,000
At-The-Market Offering [Member] | Equity Distribution Agreement [Member] | JMP Securities LLC [Member] | Maximum [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Aggregate offering price				$ 50,000,000