Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
Income Statement [Abstract]
Sales	$ 107,183	$ 100,849	$ 317,754	$ 313,363
Cost of goods sold	91,350	86,526	271,995	269,126
Gross profit	15,833	14,323	45,759	44,237
Operating expenses:
Research and development	1,410	1,309	4,156	4,003
Sales and marketing	2,561	1,805	7,344	5,215
General and administrative	8,471	9,812	26,619	22,893
Acquisition costs		2,063		2,063
Total operating expenses	12,442	14,989	38,119	34,174
Income (loss) from operations	3,391	(666)	7,640	10,063
Interest and other income (expense), net	(968)	(813)	(2,656)	(932)
Income (loss) before provision for income taxes	2,423	(1,479)	4,984	9,131
Income tax provision (benefit)	375	(356)	931	2,804
Net income (loss)	$ 2,048	$ (1,123)	$ 4,053	$ 6,327
Net income (loss) per share:
Basic	$ 0.07	$ (0.04)	$ 0.14	$ 0.25
Diluted	$ 0.07	$ (0.04)	$ 0.14	$ 0.25
Shares used in computing net income per share:
Basic	28,451	27,656	28,265	24,851
Diluted	28,979	27,656	28,879	25,493