Organization and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	May 05, 2020 USD ($) $ / shares shares	Mar. 11, 2020 Patient	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Organization And Basis Of Presentation [Line Items]
Entity incorporation, date of incorporation					Nov. 21, 2005
Net losses			$ 6,334	$ 4,163	$ 15,106	$ 11,953
Accumulated deficit			(142,863)		(142,863)		$ (127,757)
Cash and cash equivalents			$ 81,555		81,555		$ 9,808
Net proceeds from initial public offering					$ 59,892
Number of patients | Patient		67
Common Stock
Organization And Basis Of Presentation [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares | shares					4,025,000
Gross proceeds from initial public offering	$ 64,400
Net proceeds from initial public offering	$ 57,300
IPO | Common Stock
Organization And Basis Of Presentation [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares | shares	4,025,000
Shares issued and sold, public offering price | $ / shares	$ 16.00
Exercise of Underwriters' Option | Common Stock
Organization And Basis Of Presentation [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares | shares	525,000