Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]
Beginning Balance at Dec. 28, 2019	$ 773,584	$ 326	$ 52,605	$ 720,653
Beginning Balance, Shares at Dec. 28, 2019		32,556,263
Exercise of stock options, shares		10
Compensation expense under Incentive Stock Plan	1,214		1,214
Purchase and cancellation of common stock	(5,780)	$ (1)	(175)	(5,604)
Purchase and cancellation of common stock, Shares		(96,709)
Cancellations, net of issuance of non-vested stock		(21,974)
Other stock-related activity, net of tax	(418)		(190)	(228)
Other stock related activity, net of tax, Shares		(2,925)
Net income	22,775			22,775
Ending Balance at Mar. 28, 2020	791,375	$ 325	53,454	737,596
Ending Balance, Shares at Mar. 28, 2020		32,434,665
Beginning Balance at Dec. 26, 2020	$ 853,559	$ 322	64,085	789,152
Beginning Balance, Shares at Dec. 26, 2020	32,168,740	32,168,740
Exercise of stock options	$ 316		316
Exercise of stock options, shares		11,614
Compensation expense under Incentive Stock Plan	2,111		2,111
Purchase and cancellation of common stock	(3,974)	$ (1)	(69)	(3,904)
Purchase and cancellation of common stock, Shares		(38,160)
Cancellations, net of issuance of non-vested stock		(17,599)
Other stock-related activity, net of tax	(931)		1,153	(2,084)
Other stock related activity, net of tax, Shares		(9,067)
Net income	32,730			32,730
Ending Balance at Mar. 27, 2021	$ 883,811	$ 321	$ 67,596	$ 815,894
Ending Balance, Shares at Mar. 27, 2021	32,115,528	32,115,528