Components of Accrued Expenses (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Accrued Liabilities [Line Items]
Accrued compensation	$ 18,733	$ 7,538
Accrued vendor liability	1,120	2,153
Accrued professional fees	1,383	2,043
Warranty reserve	3,240	1,217	1,672
Accrued income, and other taxes	3,024	1,115
Accrued restructuring	1,497	1,037
Other accrued expenses	8,286	4,249
Total accrued expenses	$ 37,283	$ 19,352