Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax [Line Items]
Effective tax rate	22.10%	36.80%
Accounting Standards Update (“ASU”) 2016-09 [Member]
Income Tax [Line Items]
Excess tax benefit from option exercises recognized as a reduction to income tax expense	$ 19,900
Excess tax benefit recognized		$ 6,284