Balance Sheet Details - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment at cost	$ 5,431	$ 4,973
Accumulated depreciation and amortization	(1,167)	(741)
Total	4,264	4,232
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment at cost	3,494	3,494
Lab Equipment
Property Plant And Equipment [Line Items]
Property and equipment at cost	1,373	915
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment at cost	523	523
Computers and Software
Property Plant And Equipment [Line Items]
Property and equipment at cost	$ 41	$ 41

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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