CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019
Operating activities
Net loss	$ (57)	$ (4,054)
Adjustments to reconcile net loss to net cash and cash equivalents provided by (used in) operating activities:
Depreciation and amortization	2,645	2,778
Net amortization (accretion) of investment premiums and discounts	(9)	(55)
Equity-based compensation	2,186	2,260
Straight-line rent adjustment and amortization of lease incentives	(224)	(238)
Change in the fair value of acquisition-related contingent consideration	0	7
Deferred income taxes	516	552
Loss on disposal of equipment	0	87
Changes in operating assets and liabilities	2,714	(2,470)
Total adjustments	7,828	2,921
Net cash and cash equivalents provided by (used in) operating activities	7,771	(1,133)
Investing activities
Purchases of investments	(17,071)	(18,917)
Proceeds from sales and maturities of investments	17,950	18,751
Purchases of leasehold improvements and equipment	(2,329)	(3,279)
Net cash and cash equivalents used in investing activities	(1,450)	(3,445)
Financing activities
Net proceeds from issuance of common stock	1,865	1,770
Common stock repurchases	(393)	(111)
Taxes paid related to net share settlement	(364)	(296)
Payment of acquisition-related contingent consideration	0	(230)
Net cash and cash equivalents provided by financing activities	1,108	1,133
Effect of exchange rate changes on cash	49	(87)
Net increase (decrease) in cash, cash equivalents and restricted cash	7,478	(3,532)
Cash, cash equivalents and restricted cash at beginning of period	20,554	19,884
Cash, cash equivalents and restricted cash at end of period	28,032	16,352
Non-cash investing and financing activity
Additions to right-of-use-assets obtained from new operating lease liabilities	$ 128	$ 0