Company's Effective Tax Rate Differs From Statutory Federal Tax Rate (Detail) - USD ($)	12 Months Ended
	Jan. 03, 2020	Dec. 28, 2018	Dec. 29, 2017
Income Tax Disclosure [Abstract]
Tax at federal statutory rate	$ 21,880,000	$ 19,597,000	$ 28,878,000
Re-measurement of deferred tax assets to lower enacted domestic tax rate	0	0	15,137,000
Mandatory repatriation of foreign earnings	0	0	1,370,000
State taxes, net of federal benefit	4,129,000	4,391,000	2,806,000
Divestiture of foreign subsidiary	956,000	0	0
Nondeductible officer compensation	759,000	0	0
Non-deductible expenses	345,000	335,000	417,000
Non-deductible stock-based compensation	2,000	20,000	18,000
Excess tax benefit from equity incentive plans	(6,394,000)	(3,310,000)	(5,831,000)
Difference between statutory rate and foreign effective tax rate	(341,000)	(217,000)	(1,339,000)
Other	394,000	247,000	(252,000)
Total	$ 21,730,000	$ 21,063,000	$ 41,204,000
Effective tax rate	20.90%	22.60%	49.90%