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Revenue - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Apr. 30, 2019
Disaggregation Of Revenue [Line Items]
Revenue		$ 703		$ 1,356
ImmunoForge
Disaggregation Of Revenue [Line Items]
Collaborative arrangement upfront payment receivable						$ 200
ImmunoForge \| Collaborative Agreements Payment Receivable within One Year of Contract Effective Date
Disaggregation Of Revenue [Line Items]
Collaborative arrangement upfront payment receivable						$ 300
Grant Revenue
Disaggregation Of Revenue [Line Items]
Revenue		203		856
Collaborative Agreement
Disaggregation Of Revenue [Line Items]
Revenue		500		500
Collaborative Agreement \| ImmunoForge
Disaggregation Of Revenue [Line Items]
Revenue		500		500
SBIR Grants
Disaggregation Of Revenue [Line Items]
Grants from the National Institutes of Health	$ 2,800
SBIR Grants \| Grant Revenue
Disaggregation Of Revenue [Line Items]
Revenue		$ 200	$ 0	$ 900	$ 0