Note 18 - Quarterly Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Jan. 02, 2016	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014
Net sales	$ 220,020	$ 215,510	$ 222,021	$ 210,313	$ 206,620	$ 217,608	$ 220,908	$ 206,859
Gross profit	82,706	86,182	85,281	76,330	75,559	87,380	82,995	78,494
Operating Income (Loss)	29,854	8,584	36,171	29,548	26,391	40,130	33,719	33,590
Net income	$ 22,463	$ 11,324	$ 28,684	$ 19,995	$ 19,511	$ 29,940	$ 24,578	$ 25,389
Net income per share:
Basic (in dollars per share)	$ 1	$ 0.50	$ 1.26	$ 0.88	$ 0.86	$ 1.33	$ 1.09	$ 1.13
Diluted (in dollars per share)	$ 1	$ 0.50	$ 1.26	$ 0.88	$ 0.86	$ 1.32	$ 1.08	$ 1.12