CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016
Operating activities
Net income (loss)	$ 2,929	$ (9,795)
Adjustments to reconcile net income (loss) to net cash and cash equivalents used in operating activities:
Depreciation and amortization	1,973	2,658
Net amortization of investment premiums and discounts	54	63
Equity-based compensation	1,864	1,991
Change in the fair value of acquisition-related contingent consideration	102	(142)
Deferred income taxes	(1)	9
Changes in operating assets and liabilities	(10,937)	911
Total adjustments	(6,945)	5,490
Net cash and cash equivalents used in operating activities	(4,016)	(4,305)
Investing activities
Purchases of investments	(15,608)	(7,736)
Proceeds from sales and maturities of investments	14,967	18,730
Decrease in restricted cash	202
Purchases of leasehold improvements and equipment	(2,553)	(2,039)
Net cash and cash equivalents provided by (used in) investing activities	(2,992)	8,955
Financing activities
Net proceeds from issuance of common stock	1,452	715
Taxes paid related to net share settlement	(1,985)	(401)
Payment of acquisition-related contingent consideration	(2)
Net cash and cash equivalents provided by (used in) financing activities	(535)	314
Effect of exchange rate changes on cash and cash equivalents	75	23
Net increase (decrease) in cash and cash equivalents	(7,468)	4,987
Cash and cash equivalents at beginning of period	27,043	13,746
Cash and cash equivalents at end of period	$ 19,575	$ 18,733