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Financial instruments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Financial instruments (Details) - USD ($) $ in Millions	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022	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	$ (51)	$ 0	$ 4
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	(73)	0	(92)	(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	(3)	$ (8)	0	$ (10)
Other current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	319		319		$ 448
Fair value, assets	6		6		19
Other current assets \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	1,831		1,831		2,874
Fair value, assets	20		20		49
Other current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	100		100		150
Fair value, assets	3		3		12
Other non-current assets \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	8		8		3
Fair value, assets	0		0		0
Other non-current assets \| Cross currency interest rate swaps \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, assets	650		650		750
Fair value, assets	55		55		83
Other current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	470		470		221
Fair value, liabilities	4		4		1
Other current liabilities \| Foreign currency forwards \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	2,065		2,065		1,098
Fair value, liabilities	48		48		6
Other current liabilities \| Total return swap \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	217		217		183
Fair value, liabilities	8		8		$ 6
Other non-current liabilities \| Foreign currency forwards \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount, liabilities	4		4
Fair value, liabilities	$ 0		$ 0