CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Income Statement [Abstract]
Net sales	$ 246,938	$ 231,654	$ 421,350	$ 387,007
Cost of goods sold	109,413	115,377	191,367	194,103
Gross profit	137,525	116,277	229,983	192,904
Selling, general, and administrative expenses	90,992	81,277	167,288	149,120
Operating income	46,533	35,000	62,695	43,784
Interest expense	(2,657)	(5,695)	(5,767)	(11,762)
Other income (expense)	900	49	(938)	112
Income before income taxes	44,776	29,354	55,990	32,134
Income tax expense	(11,294)	(7,131)	(14,028)	(7,744)
Net income	$ 33,482	$ 22,223	$ 41,962	$ 24,390
Net income per share
Basic (in dollars per share)	$ 0.39	$ 0.26	$ 0.48	$ 0.29
Diluted (in dollars per share)	$ 0.38	$ 0.26	$ 0.48	$ 0.28
Weighted-average common shares outstanding
Basic (in shares)	86,937	84,577	86,883	84,387
Diluted (in shares)	87,477	86,227	87,469	86,042