Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 7,191	$ 7,888
Accounts receivable, net of allowances of $38 and $38, respectively	2,087	1,687
Inventory	1,118	862
Other current assets	626	638
Total current assets	11,022	11,075
Property and equipment, net	1,324	1,669
Restricted cash	435	435
Intangible assets	781	845
Other assets	18	18
Total assets	13,580	14,042
Current liabilities
Accounts payable	2,496	2,183
Accrued liabilities	3,153	3,399
Deferred revenue	1,904	2,122
Total current liabilities	7,553	7,704
Deferred revenue, net of current portion	5,654	6,149
Deferred rent, net of current portion	265	342
Total liabilities	13,472	14,195
Commitments and contingencies (Note 7)
Shareholders' equity (deficit)
Preferred stock, par value $0.001; 25,000 shares authorized; 0 and 0 shares issued and outstanding	0	0
Common stock, par value $0.001; 100,000 shares authorized; 51,759 and 47,423 shares issued and outstanding	52	47
Additional paid-in capital	490,459	483,171
Accumulated deficit	(490,403)	(483,371)
Total shareholders' equity (deficit)	108	(153)
Total liabilities and shareholders' equity (deficit)	$ 13,580	$ 14,042