Customer and Geographic Information (Details) (USD $)	3 Months Ended
	Oct. 31, 2013	Oct. 31, 2012
Major customer
Revenues from External Customers
Percentage of revenue generated from external customer type	12.50%
Minimum percentage of consolidated net sales sold to one customer or individual country requiring additional and separate disclosure	10.00%	10.00%
U.S. government
Revenues from External Customers
Percentage of revenue generated from external customer type	25.60%	43.40%
U.S. government | Combined telecommunications transmission and RF microwave amplifiers segments (excluding mobile data communications segment)
Revenues from External Customers
Percentage of revenue generated from external customer type	20.60%	36.30%
Commercial (United States)
Revenues from External Customers
Percentage of revenue generated from external customer type	17.40%	13.50%
Total United States
Revenues from External Customers
Percentage of revenue generated from external customer type	43.00%	56.90%
North African country
Revenues from External Customers
Percentage of revenue generated from external customer type	12.40%	2.30%
Other international
Revenues from External Customers
Percentage of revenue generated from external customer type	44.60%	40.80%
Total International
Revenues from External Customers
Percentage of revenue generated from external customer type	57.00%	43.10%
Revenue generated from external customers	$ 47,540,000	$ 39,217,000