Supplemental Balance Sheet Information - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total property and equipment	$ 3,553	$ 3,417
Accumulated depreciation and amortization	(2,302)	(2,081)
Property & equipment, net	1,251	1,336
Scientific Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	2,326	2,300
Furniture and Office Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	445	346
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	$ 782	$ 771