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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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 (Details) - USD ($) $ in Millions	3 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Nov. 30, 2017	Nov. 30, 2016	Aug. 31, 2017
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	$ (19)	$ 50
Foreign currency forwards \| Not Designated as Hedging Instrument \| Other income
Effect of Fair Value Hedges on Results of Operations [Abstract]
Gains and (losses) due to changes in fair value of derivative instruments	34	$ 1
Other non-current assets \| Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	0		$ 250
Fair value	0		0
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	0		24
Fair value	0		0
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	139		221
Fair value	3		0
Other current liabilities \| Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	250		0
Fair value	1		0
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	3,064		2,816
Fair value	$ 15		$ 19