Consolidated Statements of Changes in Shareholders Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock at Cost	Accumulated Other Comprehensive Income (Loss)
Beginning Balance (in shares) at Dec. 28, 2013		67,017,858			21,528,693
Beginning Balance at Dec. 28, 2013	$ 454,481	$ 670	$ 179,807	$ 1,173,044	$ (899,028)	$ (12)
Net income	138,809			138,809
Dividends	(56,479)			(56,479)
Purchases of common stock (in shares)					939,872
Purchases of common stock	(56,393)				$ (56,393)
Issuance of stock related to stock-based compensation plans, including excess tax effect (in shares)		250,959			5,766
Issuance of stock related to stock-based compensation plans, including excess tax effect	2,219	$ 3	2,408		$ (192)
Stock-based compensation	6,797		6,797
Other comprehensive income (loss)	(1,173)					(1,173)
Ending Balance (in shares) at Dec. 27, 2014		67,268,817			22,474,331
Ending Balance at Dec. 27, 2014	488,261	$ 673	189,012	1,255,374	$ (955,613)	(1,185)
Net income	147,689			147,689
Dividends	(13,088)			(13,088)
Purchases of common stock (in shares)					2,497,748
Purchases of common stock	(161,152)				$ (161,152)
Issuance of stock related to stock-based compensation plans, including excess tax effect (in shares)		122,799
Issuance of stock related to stock-based compensation plans, including excess tax effect	(95)	$ 1	(96)
Stock-based compensation	6,925		6,925
Other comprehensive income (loss)	(2,303)					(2,303)
Ending Balance (in shares) at Dec. 26, 2015		67,391,616			24,972,079
Ending Balance at Dec. 26, 2015	466,237	$ 674	195,841	1,389,975	$ (1,116,765)	(3,488)
Net income	137,350			137,350
Dividends	(14,332)			(14,332)
Purchases of common stock (in shares)					773,281
Purchases of common stock	(50,516)				$ (50,516)
Issuance of stock related to stock-based compensation plans, including excess tax effect (in shares)		194,059			2,181
Issuance of stock related to stock-based compensation plans, including excess tax effect	672	$ 2	826		$ (156)
Stock-based compensation	2,747		2,747
Other comprehensive income (loss)	399					399
Ending Balance (in shares) at Dec. 31, 2016		67,585,675			25,747,541
Ending Balance at Dec. 31, 2016	$ 542,557	$ 676	$ 199,414	$ 1,512,993	$ (1,167,437)	$ (3,089)