Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Jul. 31, 2012
Current assets:
Cash and cash equivalents	$ 32,358	$ 29,446
Marketable securities	95,386	107,728
Accounts receivable-trade, net of allowances of $0 and $39	23,523	31,182
Accounts receivable-other	647	740
Inventories	29,350	28,850
Prepaid expenses and other current assets	3,430	3,440
Total current assets	184,694	201,386
Property and equipment, net	17,744	18,229
Intangible assets, net	2,362	3,153
Goodwill	43,030	43,030
Other assets	1,248	1,270
Total assets	249,078	267,068
Current liabilities:
Accounts payable	9,082	12,734
Accrued expenses	17,382	19,736
Deferred revenue	5,030	5,347
Total current liabilities	31,494	37,817
Other long-term liabilities	12,085	13,547
Commitments and contingencies (Note 5)
Stockholders' equity:
Common stock	2,375	2,430
Additional paid-in capital	743,411	750,760
Accumulated other comprehensive income	156	230
Accumulated deficit	(540,443)	(537,716)
Total stockholders' equity	205,499	215,704
Total liabilities and stockholders' equity	$ 249,078	$ 267,068