Balance Sheet Components - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 47,708	$ 38,275
Less: accumulated depreciation	(27,140)	(26,359)
Property and equipment, net	20,568	11,916
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	16,951	16,690
Manufacturing equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	12,140	10,387
Laboratory and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,817	1,434
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	235	206
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16,565	$ 9,558

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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