Summarizes Components of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 125,173	$ 61,178
Less: accumulated depreciation	(28,149)	(18,022)
Property and equipment, net	97,024	43,156
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,158	4,158
Building and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	22,972	14,543
Software and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	15,774	8,965
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,659	9,860
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,663	2,211
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	20,937	13,633
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 40,010	$ 7,808

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.

+ References

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