Cost Reduction Actions (Activity of Facility Related Exit Costs) (Details) (USD $)	12 Months Ended			33 Months Ended
	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009	Jul. 31, 2011
Cost Reduction Actions [Abstract]
Present value of estimated facility-related exit costs, beginning balance	$ 2,136,000		$ 2,100,000	$ 2,100,000
Cash payments made	982,000			(3,296,000)
Cash payments received	1,203,000			3,284,000
Interest accreted on the facility-related exit costs	161,000	150,000	119,000	430,000
Present value of estimated facility-related exit costs, ending balance	2,518,000	2,136,000		2,518,000
Amount of facility-related exit cost liability recorded as prepaid expenses	398,000			398,000
Facility-related exit cost liability, Noncurrent	$ 2,916,000			$ 2,916,000