Supplemental information - Summary of Cash, Cash Equivalents, Marketable Securities and Restricted Cash (Details) - USD ($) $ in Millions	May 31, 2022	Aug. 31, 2021	May 31, 2021	Aug. 31, 2020
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 2,285	$ 559
Marketable securities	2,173	634
Restricted cash (included in other current assets)	82	77
Cash, cash equivalents, marketable securities and restricted cash	$ 4,541	$ 1,270	$ 1,803	$ 746

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant