Property and Equipment, Net - Components of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,788	$ 3,720
Less: Accumulated depreciation and amortization	(1,515)	(827)
Property and equipment, net	2,273	2,893
Computer Software and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	438	166
Office Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	364	210
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,636	863
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	12	897
Manufacturing Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,338	$ 1,584

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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