Income taxes - components of earnings before income tax provision (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Income Tax Disclosure [Abstract]
U.S.	$ 3,292	$ 1,953	$ 2,577
Non–U.S.	2,683	2,900	2,567
Earnings before income tax provision	$ 5,975	$ 4,853	$ 5,144

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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-Name Accounting Standards Codification
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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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