Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating activities:
Net loss	$ (13,740)	$ (4,735)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Amortization of intangible assets	0	1,687
Depreciation and amortization of property and equipment	554	924
Gain on disposal of property and equipment	(3)	(27)
Income tax benefit related to marketable securities	(60)	0
Stock-based compensation	3,379	2,631
Changes in operating assets and liabilities:
Accounts receivable, net	(1,879)	3,989
Inventories, net	19	(163)
Prepaid expenses and other current assets	(1,824)	190
Restricted cash	(27)	0
Other assets	(44)	27
Accounts payable	(446)	(492)
Accrued compensation	(1,394)	(488)
Other accrued liabilities	271	601
Long term lease incentive	(212)	(212)
Other long term liabilities	(56)	0
Deferred revenue	3,904	(3,745)
Net cash provided by (used in) operating activities	(11,558)	187
Investing activities:
Purchase of property and equipment	(680)	(474)
Proceeds from disposal of property and equipment	3	27
Changes in restricted cash	75	0
Net cash used in investing activities	(602)	(447)
Financing activities:
Proceeds from exercises of stock options	142	837
Proceeds from issuance of common stock, net of issuance costs	23,291	0
Principal payments on capital lease obligations	(60)	0
Taxes paid related to net share settlement of equity awards	(1,636)	(1,498)
Net cash provided by (used in) financing activities	21,737	(661)
Net increase (decrease) in cash and cash equivalents	9,577	(921)
Cash and cash equivalents at the beginning of the period	19,240	23,273
Cash and cash equivalents at the end of the period	28,817	22,352
Supplemental disclosure of cash flow information:
Interest paid	117	0
Supplemental noncash financing activities:
Equipment acquired under capital leases	$ 840	$ 0