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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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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Price of a single share of a number of saleable stocks of a company.

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Goodwill (Details)	12 Months Ended
Goodwill (Details)	Jul. 31, 2021 USD ($) operating_segment	Aug. 01, 2021 $ / shares
Goodwill [Roll Forward]
Balance as of July 31, 2020	$ 330,519,000
Balance as of July 31, 2021	$ 347,698,000
Number of operating segments \| operating_segment	2
Subsequent Event \| Common Stock
Goodwill [Roll Forward]
Share price (in dollars per share) \| $ / shares		$ 24.97
CGC
Goodwill [Roll Forward]
Change related to acquisitions	$ 2,222,000
Solacom
Goodwill [Roll Forward]
Change related to acquisitions	1,052,000
UHP
Goodwill [Roll Forward]
Change related to acquisitions	13,905,000
Balance as of July 31, 2021	13,905,000
Commercial Solutions
Goodwill [Roll Forward]
Balance as of July 31, 2020	255,432,000
Balance as of July 31, 2021	270,389,000
Commercial Solutions \| Subsequent Event
Goodwill [Roll Forward]
Percentage of fair value in excess of carrying amount for reporting unit		22.70%
Commercial Solutions \| CGC
Goodwill [Roll Forward]
Change related to acquisitions	0
Commercial Solutions \| Solacom
Goodwill [Roll Forward]
Change related to acquisitions	1,052,000
Commercial Solutions \| UHP
Goodwill [Roll Forward]
Change related to acquisitions	13,905,000
Government Solutions
Goodwill [Roll Forward]
Balance as of July 31, 2020	75,087,000
Balance as of July 31, 2021	77,309,000
Government Solutions \| Subsequent Event
Goodwill [Roll Forward]
Percentage of fair value in excess of carrying amount for reporting unit		94.10%
Government Solutions \| CGC
Goodwill [Roll Forward]
Change related to acquisitions	2,222,000
Government Solutions \| Solacom
Goodwill [Roll Forward]
Change related to acquisitions	0
Government Solutions \| UHP
Goodwill [Roll Forward]
Change related to acquisitions	$ 0