Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 18,873	$ 7,475
Short-term investments	13,328	38,497
Accounts receivable, net of allowances for doubtful accounts and other adjustments of $ 482 (2012) and $1,382 (2011)	8,953	8,525
Income tax receivable	681	8,293
Inventories, net of reserves for excess and obsolete inventory of $ 352 (2012) and $417 (2011)	176	309
Prepaid expenses and other current assets	903	1,138
Deferred tax asset	89	8
Total current assets	43,003	64,245
Equipment and improvements, net	11,211	15,482
Other assets	181	214
Total assets	54,395	79,941
Current liabilities:
Accounts payable	1,978	3,181
Accrued liabilities	4,829	7,641
Deferred revenue	1,436	703
Total current liabilities	8,243	11,525
Non-current liabilities:
Deferred rent and other long term liabilities	3,399	3,546
Deferred tax liability	91	10
Total non-current liabilities	3,490	3,556
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, par value $0.001 per share; 5,000,000 shares authorized; none issued or outstanding
Common stock, par value $0.001 per share; 100,000,000 shares authorized; 35,873,418 and 35,611,976 shares issued and outstanding at December 31,2012 and December 31, 2011, respectively	36	36
Additional paid-in capital	211,165	207,927
Accumulated comprehensive deficit	(168,539)	(143,103)
Total stockholders' equity	42,662	64,860
Total liabilities and stockholders' equity	$ 54,395	$ 79,941