Fair value measurements (Details) - USD ($) $ in Millions	Feb. 29, 2020	Aug. 31, 2019
Assets [Abstract]
Money market funds	$ 146	$ 217
Investments in equity securities	4	5
Level 1
Assets [Abstract]
Money market funds	146	217
Investments in equity securities	4	5
Level 2
Assets [Abstract]
Money market funds	0	0
Investments in equity securities	0	0
Level 3
Assets [Abstract]
Money market funds	0	0
Investments in equity securities	0	0
Foreign currency forwards
Assets [Abstract]
Derivative asset	59	88
Liabilities [Abstract]
Derivative liability	9	6
Foreign currency forwards \| Level 1
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Foreign currency forwards \| Level 2
Assets [Abstract]
Derivative asset	59	88
Liabilities [Abstract]
Derivative liability	9	6
Foreign currency forwards \| Level 3
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Cross currency interest rate swaps
Assets [Abstract]
Derivative asset	43	73
Liabilities [Abstract]
Derivative liability	4
Cross currency interest rate swaps \| Level 1
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0
Cross currency interest rate swaps \| Level 2
Assets [Abstract]
Derivative asset	43	73
Liabilities [Abstract]
Derivative liability	4
Cross currency interest rate swaps \| Level 3
Assets [Abstract]
Derivative asset	0	$ 0
Liabilities [Abstract]
Derivative liability	$ 0

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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, 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 55
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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities 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).

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