Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014
Operating activities
Net loss	$ (6,640)	$ (13,087)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Depreciation and amortization	3,453	3,495
Net amortization of investment premiums and discounts	265	505
Equity-based compensation	2,649	2,219
Change in the fair value of acquisition-related contingent consideration	(350)	19
Deferred income taxes	(28)	(417)
Loss on disposal of equipment	270	0
Changes in operating assets and liabilities	(53)	5,313
Total adjustments	6,206	11,134
Net cash and cash equivalents used in operating activities	(434)	(1,953)
Investing activities
Purchases of investments	(17,434)	(27,378)
Proceeds from sales and maturities of investments	25,950	39,125
Proceeds from sale of equipment	11	13
Increase in restricted cash	0	(1,000)
Purchases of leasehold improvements and equipment	(2,200)	(2,300)
Net cash and cash equivalents provided by investing activities	6,327	8,460
Financing activities
Common stock repurchases	(10,879)	(7,150)
Net proceeds from issuance of common stock	1,691	2,246
Net cash and cash equivalents used in financing activities	(9,188)	(4,904)
Effect of exchange rate changes on cash	(153)	(10)
Net increase (decrease) in cash and cash equivalents	(3,448)	1,593
Cash and cash equivalents at beginning of period	21,482	20,121
Cash and cash equivalents at end of period	$ 18,034	$ 21,714