Fair value measurements (Details) - USD ($) $ in Millions	May 31, 2021	Aug. 31, 2020
Recurring
Assets [Abstract]
Money market funds	$ 447	$ 6
Investments in equity securities	10	1
Investments in debt securities	535
Recurring \| Level 1
Assets [Abstract]
Money market funds	447	6
Investments in equity securities	10	1
Investments in debt securities	0
Recurring \| Level 2
Assets [Abstract]
Money market funds	0	0
Investments in equity securities	0	0
Investments in debt securities	0
Recurring \| Level 3
Assets [Abstract]
Money market funds	0	0
Investments in equity securities	0	0
Investments in debt securities	535
Recurring \| Foreign currency forwards
Assets [Abstract]
Derivative asset	3	20
Liabilities [Abstract]
Derivative liability	46	80
Recurring \| Foreign currency forwards \| Level 1
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Recurring \| Foreign currency forwards \| Level 2
Assets [Abstract]
Derivative asset	3	20
Liabilities [Abstract]
Derivative liability	46	80
Recurring \| Foreign currency forwards \| Level 3
Assets [Abstract]
Derivative asset	0	0
Liabilities [Abstract]
Derivative liability	0	0
Recurring \| Cross currency interest rate swaps
Assets [Abstract]
Derivative asset		16
Liabilities [Abstract]
Derivative liability	71	16
Recurring \| Cross currency interest rate swaps \| Level 1
Assets [Abstract]
Derivative asset		0
Liabilities [Abstract]
Derivative liability	0	0
Recurring \| Cross currency interest rate swaps \| Level 2
Assets [Abstract]
Derivative asset		16
Liabilities [Abstract]
Derivative liability	71	16
Recurring \| Cross currency interest rate swaps \| Level 3
Assets [Abstract]
Derivative asset		0
Liabilities [Abstract]
Derivative liability	0	0
Recurring \| Interest rate swaps
Assets [Abstract]
Derivative asset	5
Liabilities [Abstract]
Derivative liability		10
Recurring \| Interest rate swaps \| Level 1
Assets [Abstract]
Derivative asset	0
Liabilities [Abstract]
Derivative liability		0
Recurring \| Interest rate swaps \| Level 2
Assets [Abstract]
Derivative asset	5
Liabilities [Abstract]
Derivative liability		10
Recurring \| Interest rate swaps \| Level 3
Assets [Abstract]
Derivative asset	0
Liabilities [Abstract]
Derivative liability		0
Recurring \| Warrants
Assets [Abstract]
Derivative asset	2
Recurring \| Warrants \| Level 1
Assets [Abstract]
Derivative asset	0
Recurring \| Warrants \| Level 2
Assets [Abstract]
Derivative asset	2
Recurring \| Warrants \| Level 3
Assets [Abstract]
Derivative asset	0
Recurring \| Total return swap
Assets [Abstract]
Derivative asset	9
Liabilities [Abstract]
Derivative liability		1
Recurring \| Total return swap \| Level 1
Assets [Abstract]
Derivative asset	0
Liabilities [Abstract]
Derivative liability		0
Recurring \| Total return swap \| Level 2
Assets [Abstract]
Derivative asset	9
Liabilities [Abstract]
Derivative liability		1
Recurring \| Total return swap \| Level 3
Assets [Abstract]
Derivative asset	0
Liabilities [Abstract]
Derivative liability		$ 0
Carrying Value
Liabilities [Abstract]
Carrying value of long-term notes outstanding	8,900
Estimate of Fair Value Measurement
Liabilities [Abstract]
Fair value of long-term notes outstanding	$ 9,700

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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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