Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2016	Apr. 04, 2015
Operating activities
Net loss	$ (6,305)	$ (2,893)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Depreciation and amortization	1,176	1,173
Net amortization of investment premiums and discounts	36	131
Equity-based compensation	1,111	862
Change in the fair value of acquisition-related contingent consideration	16	(26)
Changes in operating assets and liabilities	1,296	(1,295)
Total adjustments	3,635	845
Net cash and cash equivalents used in operating activities	(2,670)	(2,048)
Investing activities
Purchases of investments	(2,109)	(11,476)
Proceeds from sales and maturities of investments	13,305	12,000
Purchases of leasehold improvements and equipment	(1,250)	(918)
Net cash and cash equivalents provided by (used in) investing activities	9,946	(394)
Financing activities
Net proceeds from issuance of common stock	711	834
Common stock repurchases		(2,806)
Net cash and cash equivalents used in financing activities	711	(1,972)
Effect of exchange rate changes on cash and cash equivalents	67
Net increase (decrease) in cash and cash equivalents	8,054	(4,414)
Cash and cash equivalents at beginning of period	13,746	21,482
Cash and cash equivalents at end of period	$ 21,800	$ 17,068