Property and Equipment, Net - Summary of Property and Equipment and Related Accumulated Depreciation and Amortization (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 38,167	$ 37,221
Less accumulated depreciation and amortization	(13,586)	(10,310)
Total property and equipment, net	24,581	26,911
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	957	863
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,054	2,007
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	21,564	21,025
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 13,592	11,102
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 2,224

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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