Leases - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2009 ft²
Leases [Line Items]
Percentage ceiling on rent increases, annually, capital lease	3.00%
San Carlos facility capital leases, termination date	Oct. 05, 2016
Future minimum rental receipts under the San Carlos facility subleases	$ 2.1
Book value of assets, gross	5.1	$ 2.7
Net book value of assets	$ 3.2	1.2
Operating Sublease term commenced start date	2010-08
Operating Sublease term commenced period	114 months
Operating Sublease term commenced end date	January 31, 2020
Rent expense for operating leases	$ 3.2	3.2	$ 2.9
Deferred rent	$ 8.5	$ 8.7
Pfizer, Inc. [Member]
Leases [Line Items]
Operating sublease | ft²				126,285