Basis of Presentation - Additional Information (Details)			3 Months Ended	9 Months Ended
	Sep. 18, 2020 USD ($) $ / shares shares	Sep. 08, 2020	Sep. 30, 2020 USD ($) Security shares	Sep. 30, 2020 USD ($) Security shares	Dec. 31, 2019 USD ($)
Basis Of Presentation [Line Items]
Reverse stock split, description				1-for-5.1 reverse stock split of its common stock
Reverse stock split, conversion ratio		0.196078431
Accumulated deficit			$ (109,930,000)	$ (109,930,000)	$ (83,442,000)
Cash, cash equivalents and short-term investments			109,200,000	109,200,000
Working capital			$ 106,800,000	$ 106,800,000
Number of investments unrealized loss position had other-than-temporary impairment | Security			0	0
Long-lived assets, impairment losses				$ 0
Minimum
Basis Of Presentation [Line Items]
Property and equipment, estimated useful life				3 years
Maximum
Basis Of Presentation [Line Items]
Property and equipment, estimated useful life				5 years
Series C Convertible Preferred Stock
Basis Of Presentation [Line Items]
Warrant converted into number of common stock | shares	23,122
Common Stock
Basis Of Presentation [Line Items]
Shares issued | shares			6,540,000	6,540,000
IPO | Common Stock
Basis Of Presentation [Line Items]
Shares issued | shares	6,540,000
Shares issued, offering price per share | $ / shares	$ 13.00
Net proceeds from issuance	$ 76,900,000
Underwriter's discounts and commissions	6,000,000
Stock issuance costs	$ 2,200,000
Unpaid issuance costs			$ 900,000	$ 900,000
Preferred stock automatically converted into Common Stock | shares	16,685,014