Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Apr. 01, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 35,558	$ 31,073
Restricted cash	1,877	1,877
Accounts receivable, net of allowance for doubtful accounts of $711 as of April 1, 2012 and $684 as of December 31, 2011	19,870	25,278
Advance billings	4,318	5,071
Inventories	30,816	29,203
Prepaid expenses and other current assets	7,005	9,024
Total current assets	99,444	101,526
Property and equipment, net	10,352	10,552
Intangibles, net	688	750
Other assets	923	1,015
Total assets	111,407	113,843
Current liabilities:
Accounts payable	18,331	16,785
Accrued compensation and benefits	5,889	5,781
Deferred revenue	9,582	12,117
Other current liabilities	9,814	10,666
Total current liabilities	43,616	45,349
Deferred revenues, non-current	2,983	3,158
Other long-term liabilities	5,130	5,191
Total liabilities	51,729	53,698
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, 2,000 shares authorized; none issued and outstanding	0	0
Common stock, par value $0.001, 120,000 shares authorized; 62,656 shares issued and 58,475 shares outstanding as of April 1, 2012; 62,547 shares issued and 58,366 shares outstanding as of December 31, 2011	63	63
Additional paid-in capital	650,643	650,110
Accumulated other comprehensive income	20,591	20,472
Treasury stock, 4,181 shares as of April 1, 2012 and December 31, 2011	(37,986)	(37,986)
Accumulated deficit	(573,633)	(572,514)
Total stockholders' equity	59,678	60,145
Total liabilities and stockholders' equity	$ 111,407	$ 113,843