Pfizer Stock Purchase Agreement - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Nov. 09, 2020	Nov. 09, 2020	Dec. 31, 2020	Dec. 31, 2019
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs				$ 134,524
Collaboration agreement revenue recognized			$ 2,702	$ 1,666
Pfizer Inc.
Common stock estimated fair value	$ 52,000	$ 52,000
Stock purchase agreement remaining allocated value	8,000	8,000
Allocated Information Committee obligation	$ 8,000	$ 8,000
Pfizer Inc. | Collaborative Arrangement
Collaboration agreement revenue recognized			400
Deferred revenue			$ 7,600
Private Placement
Issuance of common stock, net of discounts and issuance costs, Shares	5,000,000	5,000,000
Shares issued price per share	$ 12.00	$ 12.00
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs	$ 60,000	$ 60,000
Common stock purchase agreement condition	The shares of common stock sold to Pfizer are subject to a one-year lock-up from closing, during which time Pfizer is prohibited from selling or otherwise disposing of such shares.