Goodwill (Details) - USD ($)	Jan. 31, 2016	Aug. 01, 2015	Jul. 31, 2015
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill gross	$ 150,603,000		$ 150,603,000
Goodwill accumulated impairment	(13,249,000)		(13,249,000)
Goodwill	137,354,000		137,354,000
Telecommunications Transmission Segment
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill gross	107,779,000		107,779,000
Goodwill accumulated impairment	0		0
Goodwill	107,779,000		107,779,000
Percentage of fair value in excess of carrying value		14.00%
RF Microwave Amplifiers Segment
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill gross	29,575,000		29,575,000
Goodwill accumulated impairment	0		0
Goodwill	29,575,000		29,575,000
Percentage of fair value in excess of carrying value		14.20%
Mobile Data Communications Segment
Goodwill, Impaired, Accumulated Impairment Loss [Abstract]
Goodwill gross	13,249,000		13,249,000
Goodwill accumulated impairment	(13,249,000)		(13,249,000)
Goodwill	$ 0		$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a,h)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Percentage of fair value of reporting unit in excess of carrying amount.

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