Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Income Tax [Line Items]
Income tax provision	$ 18,873	$ 12,887
Effective tax rate	34.60%	33.10%
Potential interest and penalties accrued	$ 500		$ 400
Domestic
Income Tax [Line Items]
Gross cumulative unrecognized tax benefits	$ 7,800