Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 20,090	$ 22,130
Marketable securities, current	0	3,005
Accounts receivable, net of allowances of $548 at June 30, 2014 and $460 at December 31, 2013	2,944	5,413
Inventories	1,963	1,487
Prepaid expenses and other current assets	1,618	1,567
Assets held for sale	292	2,179
Total current assets	26,907	35,781
Restricted cash	711	711
Marketable securities, non-current	1,453	795
Property and equipment, net	4,853	8,446
Intangible assets, net	7,873	9,560
Goodwill	3,241	3,241
Other non-current assets	205	306
Total assets	45,243	58,840
Current liabilities:
Accounts payable	3,329	3,961
Accrued compensation	1,978	3,625
Other accrued liabilities	2,833	1,612
Deferred revenues	2,654	2,001
Total current liabilities	10,794	11,199
Deferred revenues, net of current portion	907	1,114
Other long-term liabilities	4,214	5,044
Total liabilities	15,915	17,357
Commitments and contingencies (note 10)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.0001 par value; 100,000 shares authorized at June 30, 2014 and December 31, 2013; 38,860 and 38,351 shares issued and outstanding at June 30, 2014 and December 31, 2013, respectively	4	4
Additional paid-in capital	300,663	298,370
Accumulated other comprehensive income (loss)	374	(32)
Accumulated deficit	(271,713)	(256,859)
Total stockholders’ equity	29,328	41,483
Total liabilities and stockholders’ equity	$ 45,243	$ 58,840