Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 1,233	$ 311	$ 1,100
Other Comprehensive (Loss) Income, Net of Tax
Foreign currency translation adjustments	(93)	(161)	11
Defined benefit pension and postretirement plans	(275)	(26)	179
Cash flow hedges	(6)	1	17
Other Comprehensive (Loss) Income, Net of Tax	(374)	(186)	206
Comprehensive Income	$ 859	$ 125	$ 1,306

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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