Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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

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Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fixed interest rate related to the interest rate derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Financial instruments - derivative instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015
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	$ 250
Fair value	0	3
Interest rate swaps \| Derivatives not designated as hedges: \| Interest expense, net
Effect of Fair Value Hedges on Results of Operations [Abstract]
Gains and losses due to changes in fair value of derivative instruments	0	0	$ 1
Foreign currency forwards \| Derivatives designated as hedges: \| Other non-current assets
Derivatives, Fair Value [Line Items]
Notional	24
Fair value	0
Foreign currency forwards \| Derivatives designated as hedges: \| Other current assets
Derivatives, Fair Value [Line Items]
Notional		1,177
Fair value		16
Foreign currency forwards \| Derivatives designated as hedges: \| Other current liabilities
Derivatives, Fair Value [Line Items]
Notional		41
Fair value		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	11	19	78
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	(48)	(12)	72
Foreign currency forwards \| Derivatives not designated as hedges: \| Other current assets
Derivatives, Fair Value [Line Items]
Notional	221
Fair value	0
Foreign currency forwards \| Derivatives not designated as hedges: \| Other current liabilities
Derivatives, Fair Value [Line Items]
Notional	2,816
Fair value	19
Basis swap \| Derivatives designated as hedges: \| Other current assets
Derivatives, Fair Value [Line Items]
Notional		2
Fair value		1
Second Step Transaction 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	$ 0	$ 0	$ (166)