Accrued Expenses and Other Current Liabilities (Details) (USD $)	Jan. 31, 2015	Jul. 31, 2014	Jan. 31, 2014	Jul. 31, 2013
Accrued Liabilities, Current [Abstract]
Accrued wages and benefits	$ 10,278,000	$ 12,410,000
Accrued warranty obligations	8,295,000	8,618,000	8,291,000	7,797,000
Accrued commissions and royalties	3,322,000	3,215,000
Other	5,664,000	5,560,000
Accrued expenses and other current liabilities	$ 27,559,000	$ 29,803,000