Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016
Intangible Assets [Line Items]
Gross carrying amount, total intangible assets	$ 7,497	$ 7,920
Net, Total Intangible Assets	6,727	7,540
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	4,873	5,215
Accumulated Amortization	(770)	(380)
Net, Total Amortized Intangible Assets	4,103	4,835
Patented Technology
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	1,231	1,528
Accumulated Amortization	(129)	(24)
Net, Total Amortized Intangible Assets	1,102	1,504
Customer Relationships
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	3,116	3,168
Accumulated Amortization	(397)	(226)
Net, Total Amortized Intangible Assets	2,719	2,942
Miscellaneous
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	526	519
Accumulated Amortization	(244)	(130)
Net, Total Amortized Intangible Assets	282	389
Trademarks/trade names
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Carrying Amount, Gross and Net	2,497	2,555
Miscellaneous
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Carrying Amount, Gross and Net	$ 127	$ 150

Intangible Assets [Line Items]

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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

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

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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