CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Oct. 01, 2016	Oct. 03, 2015
Operating activities
Net loss	$ (10,276)	$ (6,640)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Depreciation and amortization	3,744	3,453
Net amortization of investment premiums and discounts	96	265
Equity-based compensation	2,896	2,649
Change in the fair value of acquisition-related contingent consideration	(90)	(350)
Deferred income taxes	9	(28)
(Gain) loss on disposal of equipment	(8)	270
Changes in operating assets and liabilities	577	65
Total adjustments	7,224	6,324
Net cash and cash equivalents used in operating activities	(3,052)	(316)
Investing activities
Purchases of investments	(10,433)	(17,434)
Proceeds from sales and maturities of investments	22,180	25,950
Proceeds from sale of equipment	8	11
Purchases of leasehold improvements and equipment	(2,535)	(2,200)
Increase in restricted cash	(178)
Net cash and cash equivalents provided by investing activities	9,042	6,327
Financing activities
Common stock repurchases		(10,879)
Net proceeds from issuance of common stock	1,482	1,691
Taxes paid related to net share settlement	(403)	(118)
Net cash and cash equivalents used in financing activities	1,079	(9,306)
Effect of exchange rate changes on cash	8	(153)
Net increase (decrease) in cash and cash equivalents	7,077	(3,448)
Cash and cash equivalents at beginning of period	13,746	21,482
Cash and cash equivalents at end of period	$ 20,823	$ 18,034