Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 27, 2016	Mar. 29, 2015
Cash flows from operating activities:
Net income (loss)	$ (4,001)	$ 6,305
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	784	610
Stock-based compensation	519	516
Other non-cash items	(22)	253
Changes in assets and liabilities:
Accounts receivable	(4,803)	(4,820)
Advance billings	(472)	265
Inventories	929	(757)
Prepaid expenses and other assets	802	57
Accounts payable	(2,909)	(340)
Accrued compensation and benefits and other current liabilities	(3,304)	823
Deferred revenues	381	(100)
Other liabilities	169	138
Net cash provided by (used in) operating activities	(11,927)	2,950
Cash flows from investing activities:
Purchases of property and equipment	(454)	(458)
Other	3	0
Net cash used in investing activities	(451)	(458)
Cash flows from financing activities:
Proceeds from issuance of common stock, net of RSU settlements	(79)	1,225
Net cash provided by (used in) financing activities	(79)	1,225
Effect of exchange rate changes on cash and cash equivalents	36	(31)
Net increase (decrease) in cash and cash equivalents	(12,421)	3,686
Cash and cash equivalents, beginning of period	33,427	22,760
Cash and cash equivalents, end of period	21,006	26,446
Supplemental disclosure of non-cash transactions:
Transfer of inventories into property and equipment	$ 932	$ 1,988