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Revenue - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Apr. 30, 2019
Disaggregation Of Revenue [Line Items]
Revenue		$ 241	$ 411	$ 1,597	$ 411
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		241	411	1,097	411
Collaborative Agreement
Disaggregation Of Revenue [Line Items]
Revenue				500
Collaborative Agreement \| ImmunoForge
Disaggregation Of Revenue [Line Items]
Revenue		0		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	$ 400	$ 1,100	$ 400