License, Research and Collaboration Agreements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development	$ 14,904,000	$ 22,449,000
Adimab Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration agreement date	Oct. 16, 2014
Milestone payments	$ 0
Research and development milestone payments	1,500,000
Future milestone payments	2,000,000
FUJIFILM Diosynth Biotechnologies Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Future milestone payments	2,200,000
Cash payment for license agreement	2,600,000
Research and development	900,000
Other Research Agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Cash payment for license agreement	300,000
Research and development	300,000	$ 400,000
Clinical and regulatory milestone payments	$ 80,000