CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015
Operating activities
Net loss	$ (9,795)	$ (2,881)
Adjustments to reconcile net loss to net cash and cash equivalents provided by (used in) operating activities:
Depreciation and amortization	2,658	2,324
Net amortization of investment premiums and discounts	63	200
Equity-based compensation	1,991	1,663
Change in the fair value of acquisition-related contingent consideration	(142)	(200)
Deferred income taxes	9	(10)
Loss on disposal of equipment		91
Changes in operating assets and liabilities	911	(922)
Total adjustments	5,490	3,146
Net cash and cash equivalents provided by (used in) operating activities	(4,305)	265
Investing activities
Purchases of investments	(7,736)	(16,097)
Proceeds from sales and maturities of investments	18,730	20,200
Proceeds from sale of equipment		11
Purchases of leasehold improvements and equipment	(2,039)	(1,534)
Net cash and cash equivalents provided by investing activities	8,955	2,580
Financing activities
Net proceeds from issuance of common stock	715	910
Common stock repurchases		(8,868)
Taxes paid related to net share settlement	(401)	(117)
Net cash and cash equivalents used in financing activities	314	(8,075)
Effect of exchange rate changes on cash and cash equivalents	23	(35)
Net increase (decrease) in cash and cash equivalents	4,987	(5,265)
Cash and cash equivalents at beginning of period	13,746	21,482
Cash and cash equivalents at end of period	$ 18,733	$ 16,217