Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013 People	Sep. 26, 2011
Leases [Abstract]
Expiration of non-cancellable operating leases			Through 2022
Accrued lease commitments expense	$ 5.8		$ 5.8
Estimated sublease income	3.1		3.1
Rent expense under operating leases	0.3	0.6	1.0	1.8
Incentives per square feet			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					232
Time period to meet employment commitment					3 years
Extended deadline to meet employment commitment			Feb. 28, 2015