Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Income Statement [Abstract]
Net revenues	$ 247,238	$ 251,599	$ 376,301	$ 382,004
Cost of goods sold	156,979	162,369	253,120	259,869
Gross profit	90,259	89,230	123,181	122,135
Selling, general and administrative expense	54,156	52,718	99,044	100,761
Income from operations	36,103	36,512	24,137	21,374
Interest expense	99	116	210	221
Income before income taxes	36,004	36,396	23,927	21,153
Provision for income taxes	14,784	14,812	9,977	8,682
Net income	$ 21,220	$ 21,584	$ 13,950	$ 12,471
Net income per common and common equivalent share:
Basic	$ 0.84	$ 0.87	$ 0.55	$ 0.50
Diluted	$ 0.84	$ 0.86	$ 0.55	$ 0.50
Weighted average common and common equivalent shares outstanding:
Basic	25,235	24,884	25,141	24,825
Diluted	25,338	24,958	25,287	24,910