Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Details)

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Thousands				3 Months Ended	9 Months Ended
	Jan. 22, 2021 USD ($) $ / shares shares	Dec. 08, 2020 USD ($) $ / shares shares	Apr. 09, 2019 USD ($) Agreement $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) shares	Dec. 31, 2020 USD ($) shares	Nov. 30, 2019 shares
Class Of Stock [Line Items]
Gross proceeds from common stock \| $						$ 11,896
Warrants to purchase common stock				2,117,094	2,117,094	2,118,094
Remeasured fair value of warrants \| $				$ 5,594	$ 5,594		$ 19,711
Change in fair value of warrant liability \| $				$ 1,836	$ 14,117
Number of underwriting agreements \| Agreement			2
Aggregate gross proceeds from public offerings \| $			$ 70,000
Underwriting discounts and commissions and estimated offering expenses payable \| $			$ 5,000
Preferred stock, shares outstanding				0	0		0
Series A Convertible Preferred Stock
Class Of Stock [Line Items]
Preferred stock, shares outstanding				0	0			666
Class A Warrants
Class Of Stock [Line Items]
Warrants to purchase common stock				2,118,344	2,118,344
Change in fair value of warrant liability \| $					$ 9,000
Warrant exercise price of common stock per share \| $ / shares				$ 8.625	$ 8.625
Warrants exercisable date					Oct. 10, 2022
Maximum ownership percentage to total number stock issued and outstanding holder is prohibited from conversion					4.99%
Notice period for change in owning percentage					61 days
Warrants outstanding and remain unexercised excluding Oxford warrants				2,117,094	2,117,094
Weighted Average \| Class A Warrants \| Weighted Average Volatility
Class Of Stock [Line Items]
Fair value of weighted average volatility					86.06%
Weighted Average \| Class A Warrants \| Weighted Average Expected Term
Class Of Stock [Line Items]
Fair value of weighted expected term					3 years 6 months
Common Stock \| Series A Convertible Preferred Stock
Class Of Stock [Line Items]
Conversion of series A stock into common stock								666,000
Underwritten Public Offering
Class Of Stock [Line Items]
Shares issued	5,400,000
Public offering price per share \| $ / shares	$ 14.00
Gross proceeds from common stock \| $	$ 75,600
Underwriting discounts and commissions and other transaction expenses \| $	$ 5,100
Private Placement
Class Of Stock [Line Items]
Warrants to purchase common stock				2,828,125	2,828,125
Gross proceeds of private placement \| $		$ 90,500
Transaction costs \| $		$ 400
Initial fair value of warrants at issuance \| $					$ 19,300
Remeasured fair value of warrants \| $				$ 5,600	$ 5,600		$ 19,700
Private Placement \| Common Stock
Class Of Stock [Line Items]
Shares issued		10,312,500
Private Placement \| Pre-Funded Warrant
Class Of Stock [Line Items]
Warrants to purchase common stock		1,000,000
Share price (in dollars per share) \| $ / shares		$ 8.00
Private Placement \| Warrants
Class Of Stock [Line Items]
Share price (in dollars per share) \| $ / shares		$ 7.99
Private Placement \| Warrants \| Maximum
Class Of Stock [Line Items]
Warrants to purchase common stock		2,828,125
Public Offering \| Common Stock Agreement \| Class A Warrants
Class Of Stock [Line Items]
Warrants to purchase common stock			1,951,844
Share price (in dollars per share) \| $ / shares			$ 7.50
Public Offering \| Preferred Stock Agreement \| Series A Convertible Preferred Stock
Class Of Stock [Line Items]
Shares issued			666
Public Offering \| Preferred Stock Agreement \| Class A Warrants
Class Of Stock [Line Items]
Warrants to purchase common stock			166,500
Share price (in dollars per share) \| $ / shares			$ 7,500
Public Offering \| Common Stock \| Common Stock Agreement
Class Of Stock [Line Items]
Shares issued			8,667,333