Summary of major accounting policies - variable interest entities (Details) - USD ($) $ in Millions	Aug. 31, 2023	Aug. 31, 2022
Variable Interest Entity [Line Items]
Assets	$ 96,628	$ 90,124
Liabilities	68,140	59,717
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Assets	881	313
Liabilities	$ 486	$ 142

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details

- Definition

Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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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.

+ References + Details