Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning Balance at Dec. 30, 2016	$ 573,820	$ 55,834	$ 453,394	$ 206,820	$ (142,228)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued	42,973	1,164	41,809	0	0
Shares repurchased	(90,159)	(883)	(7,172)	(82,104)	0
Stock compensation cost	16,326	0	16,326	0	0
Restricted stock cancelled (issued)	(285)	0	(285)	0	0
Net Earnings	216,020	0	0	216,020	0
Dividends declared	(60,381)	0	0	(60,381)	0
Other comprehensive income (loss)	21,675	0	0	0	21,675
Ending Balance at Sep. 29, 2017	719,989	56,115	504,072	280,355	(120,553)
Beginning Balance at Jun. 30, 2017	651,562	55,991	493,329	224,822	(122,580)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued	6,733	155	6,578	0	0
Shares repurchased	(2)	(31)	(255)	(288)	0
Stock compensation cost	4,422	0	4,422	0	0
Restricted stock cancelled (issued)	(2)	0	(2)	0	0
Net Earnings	75,460	0	0	75,460	0
Dividends declared	(20,215)	0	0	(20,215)	0
Other comprehensive income (loss)	2,027	0	0	0	2,027
Ending Balance at Sep. 29, 2017	719,989	56,115	504,072	280,355	(120,553)
Beginning Balance at Dec. 29, 2017	723,063	169,319	499,934	181,599	(127,789)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued	8,092	1,592	6,500	0	0
Shares repurchased	(155,601)	(3,502)	(10,340)	(141,759)	0
Stock compensation cost	18,321	0	18,321	0	0
Restricted stock cancelled (issued)	(772)	0	(772)	0	0
Net Earnings	267,331	0	0	267,331	0
Dividends declared	(66,725)	0	0	(66,725)	0
Reclassified to retained earnings from AOCI	0	0	0	15,453	(15,453)
Other comprehensive income (loss)	2,853	0	0	0	2,853
Ending Balance at Sep. 28, 2018	796,562	167,409	513,643	255,899	(140,389)
Beginning Balance at Jun. 29, 2018	711,805	167,130	505,342	185,407	(146,074)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued	3,419	279	3,140	0	0
Shares repurchased	0	0	0	0	0
Stock compensation cost	5,161	0	5,161	0	0
Net Earnings	92,681	0	0	92,681	0
Dividends declared	(22,189)	0	0	(22,189)	0
Other comprehensive income (loss)	5,685	0	0	0	5,685
Ending Balance at Sep. 28, 2018	$ 796,562	$ 167,409	$ 513,643	$ 255,899	$ (140,389)