Collaboration Agreements - Additional Information (Details) - Surface Oncology, Inc.	1 Months Ended	3 Months Ended		6 Months Ended
	Nov. 30, 2017 TargetAntigen	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of target antigens against which antibodies are to be identified and selected | TargetAntigen	2
Upfront payments fee received | $		$ 0	$ 25,000	$ 0	$ 118,877
Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Term of research program	9 months
Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Term of research program	12 months