Accrued Expenses and Other Current Liabilities (Details) (USD $)	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Accrued Liabilities, Current [Abstract]
Accrued wages and benefits	$ 11,526,000	$ 16,467,000
Accrued warranty obligations	7,797,000	7,883,000	9,120,000
Accrued commissions and royalties	4,206,000	3,946,000
Accrued business acquisition payments	288,000	1,752,000
Other	6,075,000	10,822,000
Accrued expenses and other current liabilities	$ 29,892,000	$ 40,870,000