Acquisitions - Narrative (Details) $ in Millions	12 Months Ended
Jul. 31, 2024 USD ($) business	Jul. 31, 2023 USD ($) business
Business Acquisition [Line Items]
Number of businesses acquired \| business	10	8
Goodwill	$ 124	$ 198
Goodwill expected tax deductible amount	90	198
Revenue since acquisition date	126
Losses since acquisition date	4
Acquisition costs	5	5
United States:
Business Acquisition [Line Items]
Goodwill	91	198
Canada
Business Acquisition [Line Items]
Goodwill	$ 33	$ 0
Minimum
Business Acquisition [Line Items]
Service period (in years)	1 year
Maximum
Business Acquisition [Line Items]
Service period (in years)	3 years

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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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The number of businesses acquired by the entity during the period.

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