Property and Equipment, net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 26,814	$ 22,702
Less: accumulated depreciation	(5,461)	(2,208)
Property and equipment, net	21,353	20,494
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	397	384
Electronic Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,482	599
Vehicle
Property Plant And Equipment [Line Items]
Property and equipment, gross	76	77
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	5,854	3,917
Manufacturing Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	11,049	9,369
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	7,528	4,608
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 428	$ 3,748

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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