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
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-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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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
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a,h)
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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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

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Goodwill (Details)	3 Months Ended
Goodwill (Details)	Oct. 31, 2015 USD ($) operating_segment	Oct. 31, 2014 operating_segment	Aug. 01, 2015	Jul. 31, 2015 USD ($)	Aug. 01, 2005
Goodwill [Line Items]
Number of reportable operating segments \| operating_segment	3	3
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 [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount					14.00%
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
RF Microwave Amplifiers Segment
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount			14.20%
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
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