Cost Reduction Actions (Activity of Facility Related Exit Costs) (Details) (USD $)	3 Months Ended		6 Months Ended		51 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jul. 31, 2008
Cost Reduction Actions [Abstract]
Present value of estimated facility-related exit costs, beginning balance			$ 2,916,000		$ 2,100,000	$ 2,100,000
Cash payments made			(510,000)		(4,811,000)
Cash payments received			610,000		5,108,000
Interest accreted on the facility-related exit costs	53,000	46,000	105,000	91,000	724,000
Present value of estimated facility-related exit costs, ending balance	3,121,000		3,121,000		3,121,000	2,100,000
Amount of facility-related exit cost liability recorded as prepaid expenses	427,000		427,000		427,000
Amount recorded as other liabilities	$ 3,548,000		$ 3,548,000		$ 3,548,000