Goodwill (Details) (USD $)	Oct. 31, 2012	Jul. 31, 2012
Goodwill gross	$ 150,603,000	$ 150,603,000
Goodwill accumulated impairment	(13,249,000)	(13,249,000)
Goodwill	137,354,000	137,354,000
Number of reportable operating segments	3	3
Telecommunications Transmission Segment [Member]
Goodwill gross	107,779,000	107,779,000
Goodwill accumulated impairment	0	0
Goodwill	107,779,000	107,779,000
RF Microwave Amplifiers Segment [Member]
Goodwill gross	29,575,000	29,575,000
Goodwill accumulated impairment	0	0
Goodwill	29,575,000	29,575,000
Mobile Data Communications Segment [Member]
Goodwill gross	13,249,000	13,249,000
Goodwill accumulated impairment	(13,249,000)	(13,249,000)
Goodwill	$ 0	$ 0

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details