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 ($)	3 Months Ended		6 Months Ended
Financial instruments (Details) - USD ($)	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017	Aug. 31, 2017
Interest rate swaps \| Six-month LIBOR
Derivatives, Fair Value [Line Items]
Fair value	$ 250,000,000		$ 250,000,000
Fixed interest rate percentage	5.25%		5.25%
Foreign currency forwards \| Not designated as hedges \| 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	$ (164,000,000)	$ (2,000,000)	$ (183,000,000)	$ 47,000,000
Foreign currency forwards \| 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	(1,000,000)	$ (15,000,000)	33,000,000	$ (14,000,000)
Other non-current assets \| Interest rate swaps \| Designated as hedges
Derivatives, Fair Value [Line Items]
Notional	0		0		$ 250,000,000
Fair value	0		0		0
Other current assets \| Foreign currency forwards \| Designated as hedges
Derivatives, Fair Value [Line Items]
Notional	0		0		24,000,000
Fair value	0		0		0
Other current assets \| Foreign currency forwards \| Not designated as hedges
Derivatives, Fair Value [Line Items]
Notional	198,000,000		198,000,000		221,000,000
Fair value	1,000,000		1,000,000		0
Other current liabilities \| Interest rate swaps \| Designated as hedges
Derivatives, Fair Value [Line Items]
Notional	250,000,000		250,000,000		0
Fair value	2,000,000		2,000,000		0
Other current liabilities \| Foreign currency forwards \| Not designated as hedges
Derivatives, Fair Value [Line Items]
Notional	3,177,000,000		3,177,000,000		2,816,000,000
Fair value	$ 61,000,000		$ 61,000,000		$ 19,000,000