Income taxes (Details) - USD ($) $ in Millions	3 Months Ended
Nov. 30, 2024	Nov. 30, 2023
Income Tax Disclosure [Abstract]
Effective tax rate	12.20%	20.70%
Income taxes paid	$ 4	$ 25

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