Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Domestic Employees
Employee Benefit Plan [Line Items]
Employer contributions to plan	$ 11.4	$ 10.9	$ 9.7
Foreign Employees
Employee Benefit Plan [Line Items]
Employer contributions to plan	$ 6.3	$ 6.1	$ 6.0