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Nominal or face amount used to calculate payments on the derivative asset.

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Financial instruments (Details) - USD ($) $ in Millions	3 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Nov. 30, 2019	Nov. 30, 2018	Aug. 31, 2019
Foreign currency forwards \| Not Designated as Hedging Instrument \| Selling, general and administrative (expenses) income
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	$ (74)	$ 45
Foreign currency forwards \| Not Designated as Hedging Instrument \| Other income
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	11	$ 3
Other non-current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	805		$ 800
Fair value	26		73
Other current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	50
Fair value	0
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional			18
Fair value			1
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	1,653		3,485
Fair value	16		87
Other current liabilities \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	50
Fair value	0
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	2,519		707
Fair value	79		$ 6
Other non-current liabilities \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	207
Fair value	$ 7