Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 20,140	$ 15,889
Effective income tax rate	33.40%	35.90%
Unrecognized tax benefits	$ 27,000		$ 25,900
Decrease in unrecognized tax benefits is reasonably possible	$ 1,600