Retirement benefits - Narrative (Details) $ in Millions	9 Months Ended
May 31, 2025 USD ($)	Nov. 23, 2023 member
Defined Benefit Plan Disclosure [Line Items]
Contributions by employer	$ 448
Expected future employer contributions	$ 450
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Number of members \| member		53,000

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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+ Details

- Definition

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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