Goodwill (Details) (USD $)	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Goodwill gross	$ 150,603,000	$ 150,603,000	$ 149,253,000
Goodwill accumulated impairment	(13,249,000)	(13,249,000)	0
Goodwill earn-out payment		1,350,000
Goodwill impairment loss during the period	0	(13,249,000)	0
Goodwill	137,354,000	137,354,000	149,253,000
Number of reportable operating segments	3
Telecommunications Transmission Segment [Member]
Goodwill gross	107,779,000	107,779,000	107,779,000
Goodwill accumulated impairment	0	0	0
Goodwill earn-out payment		0
Goodwill impairment loss during the period		0
Goodwill	107,779,000	107,779,000	107,779,000
R F Microwave Amplifiers Segment [Member]
Goodwill gross	29,575,000	29,575,000	29,575,000
Goodwill accumulated impairment	0	0	0
Goodwill earn-out payment		0
Goodwill impairment loss during the period		0
Goodwill	29,575,000	29,575,000	29,575,000
Mobile Data Communications Segment [Member]
Goodwill gross	13,249,000	13,249,000	11,899,000
Goodwill accumulated impairment	(13,249,000)	(13,249,000)	0
Goodwill earn-out payment		1,350,000
Goodwill impairment loss during the period		(13,249,000)
Goodwill	$ 0	$ 0	$ 11,899,000

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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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 5: 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

Reference 1: 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.

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+ Details

- Definition

The change during the reporting period in the carrying value of goodwill. The change could be the result of new goodwill acquired, goodwill impairment during the period, goodwill written off related to the sale of a business or other adjustments to goodwill.

+ References+ Details