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Fixed interest rate related to the interest rate derivative.

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Financial instruments - derivative instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Interest rate swaps \| Six-month LIBOR
Derivatives, Fair Value [Line Items]
Fair value	$ 250
Fixed interest rate percentage	5.25%
Interest rate swaps \| Derivatives designated as hedges: \| Other non-current assets
Derivatives, Fair Value [Line Items]
Notional		$ 250
Fair value		0
Interest rate swaps \| Derivatives designated as hedges: \| Other current liabilities
Derivatives, Fair Value [Line Items]
Notional	$ 250
Fair value	1
Foreign currency forwards \| Derivatives designated as hedges: \| Other current assets
Derivatives, Fair Value [Line Items]
Notional	15	24
Fair value	0	0
Foreign currency forwards \| Derivatives not designated as hedges: \| Selling, general and administrative expense
Effect of Fair Value Hedges on Results of Operations [Abstract]
Gains and losses due to changes in fair value of derivative instruments	17	11	$ 19
Foreign currency forwards \| Derivatives not designated as hedges: \| 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	22	(48)	$ (12)
Foreign currency forwards \| Derivatives not designated as hedges: \| Other current assets
Derivatives, Fair Value [Line Items]
Notional	3,273	221
Fair value	52	0
Foreign currency forwards \| Derivatives not designated as hedges: \| Other current liabilities
Derivatives, Fair Value [Line Items]
Notional	825	2,816
Fair value	$ 4	$ 19