Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 51,226	$ 38,642
Less: Accumulated depreciation	(29,311)	(24,140)
Total property and equipment, net	21,915	14,502
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	19,305	16,214
IT Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	7,742	3,113
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	21,026	18,219
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	910	624
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 2,243	$ 472