Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases [Abstract]
Total rental expenses	$ 24.4	$ 16.7	$ 17.7
Lease expire	2022
Rental income under sublease	$ 0.2	$ 0.2	$ 1.2