Supplemental information - Depreciation and Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended
Nov. 30, 2019	Nov. 30, 2018
Supplemental Cash Flow Elements [Abstract]
Depreciation expense	$ 359	$ 356
Intangible asset and other amortization	118	134
Total depreciation and amortization expense	$ 477	$ 490

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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-Name Accounting Standards Codification
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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
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-Section 45
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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
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-Publisher FASB
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- References

No definition available.

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