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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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		9 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	May 31, 2017	May 31, 2016	May 31, 2017	May 31, 2016	Aug. 31, 2016
Interest rate swaps \| Six-month LIBOR
Derivatives, Fair Value [Line Items]
Fair value	$ 250		$ 250
Fixed interest rate percentage	5.25%		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)	$ 24	$ 28	$ (1)
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	(1)	$ 4	(15)	$ 37
Other non-current liabilities \| Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	250		250		$ 0
Fair value	0		0		0
Other non-current liabilities \| Interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	0		0		250
Fair value	0		0		3
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	133		133		1,177
Fair value	0		0		16
Other current assets \| Basis swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	0		0		2
Fair value	0		0		1
Accrued expenses and other liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	976		976		41
Fair value	5		5		0
Accrued expenses and other liabilities \| Basis swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional	2		2		0
Fair value	$ 0		$ 0		$ 0