Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Contingency [Line Items]
Effective tax rate			35.70%	36.80%
Income tax expense	$ 12,878	$ 11,149	$ 25,919	$ 21,114
Valuation allowance	$ 4,600		4,600
Excess tax benefits from stock-based awards			$ 800
Earliest Tax Year [Member] | Federal Tax Jurisdiction [Member]
Income Tax Contingency [Line Items]
Tax years subject to examination			2012
Latest Tax Year [Member] | Federal Tax Jurisdiction [Member]
Income Tax Contingency [Line Items]
Tax years subject to examination			2015