CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Operating activities
Net loss	$ (2,392)	$ (5,136)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	1,036	1,043
Net amortization (accretion) of investment premiums and discounts	(16)	(18)
Equity-based compensation	756	817
Straight-line rent adjustment and amortization of lease incentives	(85)	(19)
Deferred income taxes	332	0
Change in the fair value of acquisition-related contingent consideration	7	(1)
Loss on disposal of equipment	45	0
Changes in operating assets and liabilities	1,286	(733)
Total adjustments	3,361	1,089
Net cash provided by (used in) operating activities	969	(4,047)
Investing activities
Purchases of investments	(5,045)	(10,161)
Proceeds from sales and maturities of investments	8,396	9,328
Purchases of leasehold improvements and equipment	(371)	(592)
Net cash provided by (used in) investing activities	2,980	(1,425)
Financing activities
Proceeds from issuance of common stock	1,021	2,065
Taxes paid related to net share settlement	(28)	(333)
Payment of acquisition-related contingent consideration	(98)	0
Net cash provided by financing activities	895	1,732
Effect of exchange rate changes on cash and cash equivalents	63	105
Net increase (decrease) in cash, cash equivalents and restricted cash	4,907	(3,635)
Cash, cash equivalents and restricted cash at beginning of period	19,884	20,941
Cash, cash equivalents and restricted cash at end of period	$ 24,791	$ 17,306

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