Consolidated Statements Of Comprehensive Income (Loss) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Net product sales	$ 26,103	$ 15,025	$ 60,429	$ 39,009
Net service sales	8,913	9,057	17,775	18,825
Net sales	35,016	24,082	78,204	57,834
Cost of sales	16,457	13,202	36,141	28,917
Gross profit	18,559	10,880	42,063	28,917
Engineering and product development expenses	13,203	12,364	25,595	25,280
Selling, general and administrative expenses	9,183	8,346	19,189	17,667
Amortization of purchased intangible assets	396	791	792	1,582
Restructuring	69	141	300	187
Loss from operations	(4,292)	(10,762)	(3,813)	(15,799)
Other income (expense):
Interest expense	(57)	(42)	(107)	(82)
Interest income	224	246	485	384
Other income, net	115	199	113	352
Loss before benefit from income taxes	(4,010)	(10,359)	(3,322)	(15,145)
Net benefit from income taxes	(734)	(671)	(595)	(549)
Net loss	(3,276)	(9,688)	(2,727)	(14,596)
Net loss per share:
Basic and diluted	$ (0.07)	$ (0.20)	$ (0.06)	$ (0.30)
Weighted-average common and common equivalent shares used in computing net loss per share:
Basic and diluted	47,425	48,961	47,864	49,225
Comprehensive loss:
Net loss	(3,276)	(9,688)	(2,727)	(14,596)
Unrealized gain (loss) on marketable securities	71	110	(74)	93
Comprehensive loss	$ (3,205)	$ (9,578)	$ (2,801)	$ (14,503)