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Financial instruments (Details) - USD ($) $ in Millions	3 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Nov. 30, 2021	Nov. 30, 2020	Aug. 31, 2021
Foreign currency forwards \| Not Designated as Hedging Instrument \| Selling, general and administrative expenses
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	$ 55	$ (29)
Foreign currency forwards \| Not Designated as Hedging Instrument \| Other income (expense)
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	(1)	(9)
Total return swap \| Not Designated as Hedging Instrument \| Selling, general and administrative expenses
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	(2)	$ 13
Other non-current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	5		$ 6
Fair value, assets	0		0
Other non-current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	153		155
Fair value, assets	4		1
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	610		575
Fair value, assets	17		7
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	3,900		3,636
Fair value, assets	64		38
Other current assets \| Total return swap \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets			224
Fair value, assets			2
Other non-current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	17		23
Fair value, liabilities	0		1
Other non-current liabilities \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	633		801
Fair value, liabilities	8		23
Other current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	85		31
Fair value, liabilities	1		1
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	2,968		808
Fair value, liabilities	2		3
Other current liabilities \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	157		109
Fair value, liabilities	5		9
Other current liabilities \| Total return swap \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	271		37
Fair value, liabilities	$ 11		$ 0