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Fixed interest rate related to the interest rate derivative.

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Financial instruments (Details) - USD ($) $ in Millions	3 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Nov. 30, 2018	Nov. 30, 2017	Aug. 31, 2018
Interest rate swaps \| Six-month LIBOR
Derivatives, Fair Value [Line Items]
Fair value	$ 250
Fixed interest rate percentage	5.25%
Foreign currency forwards \| Not Designated as Hedging Instrument \| Selling, general and administrative expenses
Effect of Fair Value Hedges on Results of Operations [Abstract]
Gains and (losses) due to changes in fair value of derivative instruments	$ 45	$ (19)
Foreign currency forwards \| Not Designated as Hedging Instrument \| Other income (expense)
Effect of Fair Value Hedges on Results of Operations [Abstract]
Gains and (losses) due to changes in fair value of derivative instruments	3	$ 34
Other current liabilities \| Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	250		$ 250
Fair value	2		1
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	816		825
Fair value	5		4
Other non-current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	400
Fair value	3
Other non-current liabilities \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	100
Fair value	0
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional			15
Fair value			0
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	2,476		3,273
Fair value	$ 65		$ 52