Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Contingency [Line Items]
Effective tax rate			34.20%	34.70%
Income tax expense (benefit)	$ 15,760	$ 12,432	$ 29,506	$ 25,170
Decrease in effective tax rate due to increase in domestic production activities deduction			0.50%
Excess tax benefits from stock based awards			$ 1,000	$ 800
Valuation allowance	$ 4,100		$ 4,100
Earliest Tax Year [Member] | Federal Tax Jurisdiction [Member]
Income Tax Contingency [Line Items]
Tax years subject to examination			2013
Latest Tax Year [Member] | Federal Tax Jurisdiction [Member]
Income Tax Contingency [Line Items]
Tax years subject to examination			2016