Goodwill And Other Intangibles (Schedule Of Change In Carry Amount Of Goodwill By Business Segment) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 3,909	$ 3,847
Acquisitions	1,486	83
Divestitures	(142)
Foreign currency translation and other	63	(21)
Goodwill, ending balance	5,316	3,909
Automation Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	3,160	3,138
Acquisitions	1,486	39
Divestitures	0
Foreign currency translation and other	58	(17)
Goodwill, ending balance	4,704	3,160
Commercial & Residential Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	749	709
Acquisitions	0	44
Divestitures	(142)
Foreign currency translation and other	5	(4)
Goodwill, ending balance	612	749
Climate Technologies [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	553	513
Acquisitions	0	44
Divestitures	0
Foreign currency translation and other	2	(4)
Goodwill, ending balance	555	553
Tools & Home Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	196	196
Acquisitions	0	0
Divestitures	(142)
Foreign currency translation and other	3	0
Goodwill, ending balance	$ 57	$ 196

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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