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Financial instruments (Details) - USD ($) $ in Millions	3 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Nov. 30, 2022	Nov. 30, 2021	Aug. 31, 2022
Foreign currency forwards \| Not Designated as Hedging Instrument \| Selling, general and administrative expense
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	$ 0	$ 55
Foreign currency forwards \| Not Designated as Hedging Instrument \| Other income, net
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	(18)	(1)
Total return swap \| Not Designated as Hedging Instrument \| Selling, general and administrative expense
Derivatives, Fair Value [Line Items]
Gains and (losses) due to changes in fair value of derivative instruments	4	$ (2)
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	168		$ 448
Fair value, assets	3		19
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	1,476		2,874
Fair value, assets	22		49
Other current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets			150
Fair value, assets			12
Other current assets \| Total return swap \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	178
Fair value, liabilities	5
Other non-current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	5
Notional amount, liabilities			3
Fair value, assets	0
Fair value, liabilities			0
Other non-current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	750
Notional amount, liabilities			750
Fair value, assets	70
Fair value, liabilities			83
Other current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets			221
Notional amount, liabilities	727
Fair value, assets			1
Fair value, liabilities	15
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	2,520		1,098
Fair value, liabilities	41		6
Other current liabilities \| Total return swap \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities			183
Fair value, liabilities			$ 6
Other non-current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	5
Fair value, liabilities	$ 0