Goodwill (Details)	3 Months Ended
Oct. 31, 2021 USD ($) operating_segment	Aug. 01, 2020 $ / shares
Goodwill [Roll Forward]
Balance as of July 31, 2021	$ 347,698,000
Balance as of October 31, 2021	$ 347,692,000
Number of operating segments \| operating_segment	2
UHP
Goodwill [Roll Forward]
Balance as of July 31, 2021	$ 13,905,000
Change related to acquisition	(6,000)
Balance as of October 31, 2021	13,899,000
Common Stock
Goodwill [Roll Forward]
Share price (in dollars per share) \| $ / shares		$ 24.97
Commercial Solutions
Goodwill [Roll Forward]
Balance as of July 31, 2021	270,389,000
Balance as of October 31, 2021	270,383,000
Percentage of fair value in excess of carrying amount for reporting unit		22.70%
Commercial Solutions \| UHP
Goodwill [Roll Forward]
Change related to acquisition	(6,000)
Government Solutions
Goodwill [Roll Forward]
Balance as of July 31, 2021	77,309,000
Balance as of October 31, 2021	77,309,000
Percentage of fair value in excess of carrying amount for reporting unit		94.10%
Government Solutions \| UHP
Goodwill [Roll Forward]
Change related to acquisition	$ 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.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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