Related parties (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Related Party Transactions [Abstract]
Purchases, net	$ 59,569	$ 57,429	$ 53,161
Trade accounts payable, net	$ 6,390	$ 6,484	$ 6,274

Amount for accounts payable to related parties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant