Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 24, 2016	Jun. 30, 2017	Jun. 24, 2016
Income Statement [Abstract]
Sales	$ 228,261	$ 129,831	$ 432,855	$ 242,060
Cost of goods sold	184,890	110,810	351,989	208,469
Gross profit	43,371	19,021	80,866	33,591
Operating expenses:
Research and development	2,774	2,359	5,680	4,635
Sales and marketing	3,351	2,785	6,402	5,718
General and administrative	12,841	10,158	24,606	20,217
Total operating expenses	18,966	15,302	36,688	30,570
Income from operations	24,405	3,719	44,178	3,021
Interest and other income (expense), net	(1,120)	(836)	(2,058)	(1,927)
Income before provision for income taxes	23,285	2,883	42,120	1,094
Income tax provision	3,106	2,160	7,600	3,610
Net income (loss)	$ 20,179	$ 723	$ 34,520	$ (2,516)
Net income (loss) per share:
Basic	$ 0.60	$ 0.02	$ 1.04	$ (0.08)
Diluted	$ 0.59	$ 0.02	$ 1.01	$ (0.08)
Shares used in computing net income (loss) per share:
Basic	33,433	32,565	33,247	32,437
Diluted	34,064	32,792	34,017	32,437