Commitments and Contingencies - Additional Information (Detail) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) $ / ft²	Sep. 30, 2014 USD ($)	Dec. 31, 2013 People	Sep. 26, 2011 USD ($)
Leases [Abstract]
Expiration of non-cancellable operating leases			Through 2022
Accrued lease commitments expense	$ 5.0		$ 5.0
Estimated sublease income	2.6		2.6
Rent expense under operating leases	$ 0.3	$ 0.3	$ 1.0	$ 1.0
Incentives per square feet | $ / ft²			40.00
Incentives for improvements to space			$ 2.2
Lease agreement term			10 years
Amount received to start-up new facility						$ 1.0
Minimum number of people to be employed | People					232
Time period to meet employment commitment					3 years
New deadline to meet employment commitment			Apr. 30, 2016