Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 14,924	$ 14,354
Restricted cash	2,075	1,877
Accounts receivable, net of allowance for doubtful accounts of $555 as of June 30, 2013 and $541 as of December 31, 2012	10,453	15,660
Advance billings	2,355	1,720
Inventories	33,176	33,309
Prepaid expenses and other current assets	4,628	4,561
Total current assets	67,611	71,481
Property and equipment, net	6,493	7,387
Intangibles, net	375	500
Other assets	895	701
Total assets	75,374	80,069
Current liabilities:
Accounts payable	14,405	11,767
Accrued compensation and benefits	2,994	4,496
Deferred revenues, current	6,661	6,189
Revolving credit facility	10,000	0
Other current liabilities	4,133	7,518
Total current liabilities	38,193	29,970
Deferred revenues, non-current	2,619	3,059
Other long-term liabilities	3,524	3,748
Total liabilities	44,336	36,777
Commitments and contingencies (Note 7)
Stockholders' equity:
Preferred stock, 2,000 shares authorized; none issued and outstanding	0	0
Common stock, par value $0.001, 120,000 shares authorized; 63,190 shares issued and 59,009 shares outstanding as of June 30, 2013; 62,908 shares issued and 58,727 shares outstanding as of December 31, 2012	63	63
Additional paid-in capital	653,024	652,041
Accumulated other comprehensive income	20,845	21,007
Treasury stock, 4,181 shares as of June 30, 2013 and December 31, 2012	(37,986)	(37,986)
Accumulated deficit	(604,908)	(591,833)
Total stockholders' equity	31,038	43,292
Total liabilities and stockholders' equity	$ 75,374	$ 80,069