Cost Reduction Actions (Summary of Radyne Acquisition Related Restructuring Plan) (Details) (USD $)	3 Months Ended
	Oct. 31, 2008	Apr. 30, 2012	Jul. 31, 2011	Jul. 31, 2008
Cost Reduction Actions [Abstract]
Business acquisition restructuring costs, total estimated costs	$ 2,713,000
Business acquisition restructuring costs related to severance for employees	613,000
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	4,286,000
Less: Interest expense to be accreted	(2,041,000)
Present value of estimated facility-related exit costs	$ 2,100,000	$ 2,815,000	$ 2,518,000	$ 2,100,000
Radyne lease expiration date	Oct. 31, 2018
Radyne sublease expiration date	Oct. 31, 2015