Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 16,685	$ 8,349
Accounts receivable, net of allowances of $52 and $52	478	669
Inventory	432	116
Other current assets	541	491
Total current assets	18,136	9,625
Property and equipment, net	1,025	894
Restricted cash	435	435
Intangible assets	941	973
Other assets	18	18
Total assets	20,555	11,945
Current liabilities
Accounts payable	2,152	1,626
Accrued liabilities	2,948	2,729
Deferred revenue	1,224	0
Billings on uncompleted contracts in excess of related costs	409	230
Total current liabilities	6,733	4,585
Deferred revenue, net of current portion	6,902	0
Deferred rent, net of current portion	453	488
Total liabilities	14,088	5,073
Commitments and contingencies (Note 7)
Shareholders' equity
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; 46,177 and 44,758 shares issued and outstanding	46	45
Additional paid-in capital	479,212	475,656
Accumulated deficit	(472,791)	(468,829)
Total shareholders' equity	6,467	6,872
Total liabilities and shareholders' equity	$ 20,555	$ 11,945