Supplemental information - Depreciation and Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2025	May 31, 2024	May 31, 2025	May 31, 2024
Supplemental Cash Flow Elements [Abstract]
Depreciation expense	$ 359	$ 369	$ 1,086	$ 1,120
Intangible assets amortization	214	238	722	717
Total depreciation and amortization expense	$ 573	$ 607	$ 1,809	$ 1,837