Fair value measurements (Details) - USD ($) $ in Millions	Feb. 28, 2023	Aug. 31, 2022
Carrying Value
Liabilities [Abstract]
Fair value of long-term notes outstanding	$ 7,600
Estimate of Fair Value Measurement
Liabilities [Abstract]
Carrying value of long-term notes outstanding	6,800
Recurring
Assets [Abstract]
Money market funds	752	$ 1,114
Investments in equity securities		1
Investments in debt securities		130
Level 1 \| Recurring
Assets [Abstract]
Money market funds	752	1,114
Investments in equity securities		1
Investments in debt securities		0
Level 2 \| Recurring
Assets [Abstract]
Money market funds	0	0
Investments in equity securities		0
Investments in debt securities		130
Level 3 \| Recurring
Assets [Abstract]
Money market funds	0	0
Investments in equity securities		0
Investments in debt securities		0
Foreign currency forwards \| Recurring
Assets [Abstract]
Derivative asset	27	69
Liabilities [Abstract]
Derivative liability	52	7
Foreign currency forwards \| Level 1 \| Recurring
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Foreign currency forwards \| Level 2 \| Recurring
Assets [Abstract]
Derivative asset	27	69
Liabilities [Abstract]
Derivative liability	52	7
Foreign currency forwards \| Level 3 \| Recurring
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Cross currency interest rate swaps \| Recurring
Assets [Abstract]
Derivative asset	58	96
Cross currency interest rate swaps \| Level 1 \| Recurring
Assets [Abstract]
Derivative asset	0	0
Cross currency interest rate swaps \| Level 2 \| Recurring
Assets [Abstract]
Derivative asset	58	96
Cross currency interest rate swaps \| Level 3 \| Recurring
Assets [Abstract]
Derivative asset	0	0
Total return swap \| Recurring
Liabilities [Abstract]
Derivative liability	8	6
Total return swap \| Level 1 \| Recurring
Liabilities [Abstract]
Derivative liability	0	0
Total return swap \| Level 2 \| Recurring
Liabilities [Abstract]
Derivative liability	8	6
Total return swap \| Level 3 \| Recurring
Liabilities [Abstract]
Derivative liability	$ 0	$ 0

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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