Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Net revenue:
Product	$ 509,527	$ 526,725	$ 494,675
Engineering	8,021	23,638	21,896
Total net revenue	517,548	550,363	516,571
Cost of sales:
Product	290,951	313,458	302,288
Engineering	6,894	20,226	21,099
Total cost of sales	297,845	333,684	323,387
Gross profit	219,703	216,679	193,184
Operating expenses:
Research and product development	73,828	63,990	57,230
Selling and marketing	59,157	51,268	44,238
General and administrative	54,147	52,527	51,753
Restructuring	3,483	3,519
Total operating expenses	190,615	171,304	153,221
Income from operations	29,088	45,375	39,963
Other (expense) income:
Interest income, net	253	371	532
(Loss) Gain on investments	(484)		2,500
Other, net	181	(1,649)	1,204
Total other (expense) income, net	(50)	(1,278)	4,236
Income before income taxes	29,038	44,097	44,199
(Benefit from) provision for income taxes	(5,442)	12,976	1,128
Net income	$ 34,480	$ 31,121	$ 43,071
Net income per common share:
Basic	$ 2.78	$ 2.54	$ 3.51
Diluted	$ 2.72	$ 2.48	$ 3.42
Weighted average shares outstanding:
Basic	12,404	12,247	12,265
Diluted	12,667	12,569	12,576
Dividends declared and paid per share:	$ 0.40	$ 0.40	$ 0.40