Goodwill and Other Intangibles - Summary of Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 1,537	$ 1,546
Accumulated amortization	(656)	(639)
Net carrying amount	881	907
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Intangible Assets, Gross (Excluding Goodwill)	1,815	1,824
Intangibles	1,159	1,185
Trademarks and Trade Names [Member]
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Trademarks and trade names	278	278
Trademarks and Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	66	66
Accumulated amortization	(25)	(25)
Net carrying amount	41	41
Intellectual Property [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	718	721
Accumulated amortization	(360)	(350)
Net carrying amount	358	371
Customer and supplier relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	753	759
Accumulated amortization	(271)	(264)
Net carrying amount	$ 482	$ 495

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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