Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Impairment of Long-Lived Assets (Details) - USD ($) $ in Millions	3 Months Ended						12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Asset impairment charge	$ 9		$ 6			$ 66
Impairment of assets held for sale		$ 21		$ 6	$ 12		$ 21	$ 18
Fixed asset impairment charges						62		66
Americas
Restructuring Cost and Reserve [Line Items]
Impairment of assets held for sale		12
China
Restructuring Cost and Reserve [Line Items]
Impairment of assets held for sale		9
Customer relationships
Restructuring Cost and Reserve [Line Items]
Impairment of definite-lived intangible assets						$ 4
Asia
Restructuring Cost and Reserve [Line Items]
Asset impairment charge			27
Impairment of assets held for sale								$ 12
Asia \| Miscellaneous
Restructuring Cost and Reserve [Line Items]
Asset impairment charge			24
Asia \| China
Restructuring Cost and Reserve [Line Items]
Asset impairment charge		$ 5
Asia \| China \| Noncurrent assets
Restructuring Cost and Reserve [Line Items]
Asset impairment charge			$ 3