Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings/(Accumulated Deficit) [Member]	Treasury Stock [Member]
Beginning Balance at Dec. 29, 2018	$ 385,544	$ 607	$ 409,661	$ (3,065)	$ (8,900)	$ (12,759)
Beginning Balance, Shares at Dec. 29, 2018		58,081,540
Vesting of restricted stock, Shares		164,226
Grants of restricted stock		$ 5	(5)
Purchases of treasury stock	(6,055)					(6,055)
Purchases of treasury stock, Shares		(428,059)
Retirement of treasury stock			(505)			505
Stock-based compensation	3,246		3,246
Exercise of stock options	1,262	$ 5	1,257
Exercise of stock options, Shares		532,931
Common stock issued under ESPP	46		46
Common stock issued under ESPP, Shares		3,165
Net income	40,408				40,408
Other comprehensive income	1,181			1,181
Ending Balance at Sep. 28, 2019	425,632	$ 617	413,700	(1,884)	31,508	(18,309)
Ending Balance, Shares at Sep. 28, 2019		58,353,803
Beginning Balance at Jun. 29, 2019	414,375	$ 615	412,295	(2,178)	16,402	(12,759)
Beginning Balance, Shares at Jun. 29, 2019		58,535,669
Purchases of treasury stock	(5,550)					(5,550)
Purchases of treasury stock, Shares		(393,819)
Stock-based compensation	970		970
Exercise of stock options	422	$ 2	420
Exercise of stock options, Shares		210,931
Common stock issued under ESPP	15		15
Common stock issued under ESPP, Shares		1,022
Net income	15,106				15,106
Other comprehensive income	294			294
Ending Balance at Sep. 28, 2019	425,632	$ 617	413,700	(1,884)	31,508	(18,309)
Ending Balance, Shares at Sep. 28, 2019		58,353,803
Beginning Balance at Dec. 28, 2019	431,548	$ 619	414,688	(238)	34,788	(18,309)
Beginning Balance, Shares at Dec. 28, 2019		58,504,734
Vesting of restricted stock, Shares		219,977
Grants of restricted stock		$ 6	(6)
Forfeitures of restricted stock		$ (2)	2
Purchases of treasury stock	(815)					(815)
Purchases of treasury stock, Shares		(51,479)
Retirement of treasury stock		$ (1)	(814)			815
Stock-based compensation	4,369		4,369
Exercise of stock options	$ 549	$ 3	546
Exercise of stock options, Shares	274,353	274,353
Common stock issued under ESPP	$ 119		119
Common stock issued under ESPP, Shares		15,191
Net income	35,121				35,121
Other comprehensive income	463			463
Ending Balance at Oct. 03, 2020	471,354	$ 625	418,904	225	69,909	(18,309)
Ending Balance, Shares at Oct. 03, 2020		58,962,776
Beginning Balance at Jul. 04, 2020	451,010	$ 626	417,452	(1,346)	52,587	(18,309)
Beginning Balance, Shares at Jul. 04, 2020		58,962,776
Forfeitures of restricted stock		$ (1)	1
Stock-based compensation	$ 1,451		1,451
Exercise of stock options, Shares	0
Net income	$ 17,322				17,322
Other comprehensive income	1,571			1,571
Ending Balance at Oct. 03, 2020	$ 471,354	$ 625	$ 418,904	$ 225	$ 69,909	$ (18,309)
Ending Balance, Shares at Oct. 03, 2020		58,962,776