Company's Effective Tax Rate Differs From Statutory Federal Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2016	Jan. 01, 2016	Jan. 02, 2015
Schedule Of Company Effective Tax Rate Differs From Statutory Federal Tax Rate [Line Items]
Tax at federal statutory rate	$ 24,193	$ 24,897	$ 23,788
State taxes, net of federal benefit	2,423	2,910	3,226
Tax exempt interest income	(7)	(23)	(44)
Non-deductible expenses	274	261	289
Non-deductible stock-based compensation	11	(42)	0
Excess tax benefit from equity incentive plans	(4,321)	0	0
Difference between statutory rate and foreign effective tax rate	(889)	(897)	(174)
Other	(42)	428	179
Total	$ 21,642	$ 27,534	$ 27,264
Effective tax rate	31.30%	38.70%	40.10%