Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 30, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Effective income tax rate	34.50%	37.60%
Estimated annual effective income tax rates				38.10%
Accounting Standards Update 2016-09
Income Taxes [Line Items]
Excess tax benefit from stock-based awards	$ 868
Scenario, Forecast
Income Taxes [Line Items]
Effective income tax rate			37.80%