Cost Reduction Actions (Present Value of Estimated Facility Related Exit Costs) (Details) (USD $)	3 Months Ended
	Oct. 31, 2008	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2008
Cost Reduction Actions [Abstract]
Total non-cancelable lease obligations	$ 12,741,000
Less: Estimated sublease income	(8,600,000)
Total net estimated facility-related exit costs	4,141,000	4,128,000
Less: Interest expense to be accreted	(2,041,000)
Present value of estimated facility-related exit costs	$ 2,100,000	$ 2,518,000	$ 2,136,000	$ 2,100,000
Radyne lease expiration date	Oct. 31, 2018
Radyne sublease expiration date	Oct. 31, 2015