Commitments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Line Items]
Rent expense	$ 58,133	$ 58,050	$ 57,226
Short term committed purchase obligations	69,926
Contribution by employer for employee saving plan	$ 8,658	$ 8,262	$ 7,768
Buildings
Commitments and Contingencies Disclosure [Line Items]
Terms of operating leases expiring year	Dec. 31, 2025
Land
Commitments and Contingencies Disclosure [Line Items]
Terms of operating leases expiring year	Dec. 31, 2057