Discontinued Operations Discontinued Operations, Alternative Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation and amortization	$ 825	$ 824	$ 919
Pension and postretirement benefit expense (income)	515	(170)	(533)
Equity in earnings of partially-owned affiliates	34	128	92
Deferred income taxes	612	(739)	573
Non-cash restructuring and impairment charges	235	36	71
Equity-based compensation	95	106	134
Accrued income taxes	(1,222)	855	(753)
Other	(29)	35	12
Capital expenditures	$ (586)	$ (645)	$ (760)

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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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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