Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 21,346	$ 31,468
Short-term investments	9,043	26,036
Accounts receivable, net of allowances for doubtful accounts of $45 and $115 at September 30, 2012 and December 31, 2011, respectively	7,490	6,092
Inventory	3,838	2,121
Current portion of restricted cash		1,266
Other current assets	2,314	4,968
Total current assets	44,031	71,951
Fixed assets, net	5,288	4,881
Restricted cash	1,100	1,100
Other assets	6,742	5,443
Total assets	57,161	83,375
Current liabilities:
Accounts payable and accrued expenses	10,949	15,318
Current portion of deferred revenue	5,943	6,637
Current portion of long-term obligations	399	101
Other current liabilities		1,709
Total current liabilities	17,291	23,765
Deferred revenue	6,906	9,265
Notes payable	77,191	75,372
Long-term obligations	1,045
Deferred rent and other long-term liabilities	3,087	2,372
Total liabilities	105,520	110,774
Commitments and contingencies
Stockholders' deficit:
Preferred stock, $0.01 par value; 1,000,000 shares authorized; 0 shares issued and outstanding
Common stock, $0.01 par value; 200,000,000 shares authorized; 99,140,550 and 98,798,065 shares issued and outstanding at September 30, 2012 and December 31, 2011, respectively	991	988
Additional paid-in capital	451,996	448,527
Accumulated deficit	(501,352)	(476,921)
Accumulated other comprehensive income	6	7
Total stockholders' deficit	(48,359)	(27,399)
Total liabilities and stockholders' deficit	$ 57,161	$ 83,375