CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2012	Jan. 31, 2011
Net revenue:
Product	$ 122,189	$ 111,315	$ 236,196	$ 208,004
Engineering	4,244	5,938	8,094	13,071
Total net revenue	126,433	117,253	244,290	221,075
Cost of sales:
Product	75,705	70,596	146,936	129,652
Engineering	3,883	5,848	7,483	11,595
Total cost of sales	79,588	76,444	154,419	141,247
Gross profit	46,845	40,809	89,871	79,828
Operating expenses:
Research and product development	13,940	14,769	29,207	28,673
Selling and marketing	10,605	10,716	21,070	20,324
General and administrative	14,509	9,320	26,219	19,067
Restructuring		(134)		3,428
Total operating expenses	39,054	34,671	76,496	71,492
Income from operations	7,791	6,138	13,375	8,336
Other income (expense):
Interest income, net	133	188	269	406
Gain on sale of other investments	2,500		2,500
Other, net	322	(100)	497	(376)
Total other income, net	2,955	88	3,266	30
Income from continuing operations before income taxes	10,746	6,226	16,641	8,366
Provision for (benefit from) income taxes	(8,869)	930	(7,000)	1,689
Income from continuing operations	19,615	5,296	23,641	6,677
Income from discontinued operations (net of income tax provision of $168)				289
Gain on disposal of discontinued operations (net of income tax provision of $505)				924
Net income	$ 19,615	$ 5,296	$ 23,641	$ 7,890
Basic net income per share:
Income from continuing operations	$ 1.61	$ 0.42	$ 1.90	$ 0.53
Income from discontinued operations, net of tax				$ 0.02
Gain on disposal of discontinued operations, net of tax				$ 0.08
Basic net income per share	$ 1.61	$ 0.42	$ 1.90	$ 0.63
Diluted net income per share:
Income from continuing operations	$ 1.59	$ 0.42	$ 1.88	$ 0.53
Income from discontinued operations, net of tax				$ 0.02
Gain on disposal of discontinued operations, net of tax				$ 0.07
Diluted net income per share	$ 1.59	$ 0.42	$ 1.88	$ 0.62
Weighted average shares outstanding:
Basic	12,188	12,574	12,464	12,599
Diluted	12,333	12,655	12,595	12,672