Income taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
May 31, 2024	May 31, 2025	May 31, 2024
Income Tax Disclosure [Abstract]
Effective tax rate	8.00%	(0.40%)	6.30%
Income taxes paid		$ 162	$ 238

Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-2A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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