Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases [Line Items]
Rent expense for noncancelable operating leases	$ 14.1	$ 12.5	$ 9.8
Minimum [Member]
Leases [Line Items]
Lease renewable period, maximum (in years)	1 year
Maximum [Member]
Leases [Line Items]
Lease renewable period, maximum (in years)	5 years