CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Income Statement [Abstract]
Net sales	$ 229,125	$ 196,109	$ 616,132	$ 537,654
Cost of goods sold	109,049	98,568	303,152	282,354
Gross profit	120,076	97,541	312,980	255,300
Selling, general, and administrative expenses	86,071	69,417	235,191	190,746
Operating income	34,005	28,124	77,789	64,554
Interest expense	(5,319)	(7,755)	(17,081)	(24,474)
Other expense	(304)	(214)	(192)	(325)
Income before income taxes	28,382	20,155	60,516	39,755
Income tax expense	(7,080)	(3,125)	(14,824)	(7,161)
Net income	$ 21,302	$ 17,030	$ 45,692	$ 32,594
Net income per share
Basic (in dollars per share)	$ 0.25	$ 0.21	$ 0.54	$ 0.40
Diluted (in dollars per share)	$ 0.25	$ 0.21	$ 0.53	$ 0.39
Weighted-average common shares outstanding
Basic (in shares)	85,285	81,147	84,686	81,238
Diluted (in shares)	86,373	82,924	86,152	82,946