Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2012	Jul. 31, 2012
Intangible Assets by Major Class [Line Items]
Cost	$ 47,138	$ 47,138
Accumulated Amortization	13,564	12,798
Net	33,574	34,340
Developed Technology Rights
Intangible Assets by Major Class [Line Items]
Cost	12,191	12,191
Accumulated Amortization	5,277	4,974
Net	6,914	7,217
Customer Relationships
Intangible Assets by Major Class [Line Items]
Cost	25,440	25,440
Accumulated Amortization	8,287	7,824
Net	17,153	17,616
Trade Names
Intangible Assets by Major Class [Line Items]
Cost	7,607	7,607
Net	7,607	7,607
In Process Research And Development
Intangible Assets by Major Class [Line Items]
Cost	1,900	1,900
Net	$ 1,900	$ 1,900