CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jul. 31, 2012	Jul. 31, 2011
Current assets:
Cash and cash equivalents	$ 136,654	$ 60,765
Short-term investments	234,965	335,847
Accounts receivable, net of allowance for doubtful accounts of $42 at July 31, 2012 and $72 at July 31, 2011	7,785	8,764
Inventories, net	8,469	11,537
Prepaid expenses and other current assets	1,589	1,770
Total current assets	389,462	418,683
Property and equipment, net	4,276	5,978
Long-term investments	67,774	44,786
Other assets	422	290
Total assets	461,934	469,737
Current liabilities:
Accounts payable	1,432	1,664
Accrued compensation	2,836	2,325
Accrued warranty	1,072	1,140
Accrued expenses	2,248	1,889
Accrued restructuring costs		294
Deferred revenue	7,871	9,141
Other current liabilities	813	1,013
Total current liabilities	16,272	17,466
Long-term deferred revenue	1,469	1,812
Long-term liabilities	1,962	1,702
Total liabilities	19,703	20,980
Commitments and contingencies (Notes 5 and 12)
Stockholders' equity:
Preferred stock, $.01 par value; 5,000 shares authorized, none issued and outstanding at July 31, 2012 and July 31, 2011
Common stock, $.001 par value; 250,000 shares authorized, 28,879 and 28,739 shares issued and outstanding at July 31, 2012 and July 31, 2011, respectively	29	29
Additional paid-in capital	1,589,357	1,583,124
Accumulated deficit	(1,146,882)	(1,133,958)
Accumulated other comprehensive loss	(273)	(438)
Total stockholders' equity	442,231	448,757
Total liabilities and stockholders' equity	$ 461,934	$ 469,737