Goodwill And Other Intangibles (Schedule Of Change In Carry Amount Of Goodwill By Business Segment) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 6,536	$ 6,455
Acquisitions	82	210
Foreign currency translation and other	116	(129)
Goodwill, ending balance	6,734	6,536
Automation Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	5,467	5,355
Acquisitions	23	210
Foreign currency translation and other	93	(98)
Goodwill, ending balance	5,583	5,467
Commercial & Residential Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	1,069	1,100
Acquisitions	59	0
Foreign currency translation and other	23	(31)
Goodwill, ending balance	1,151	1,069
Climate Technologies [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	668	670
Acquisitions	59	0
Foreign currency translation and other	3	(2)
Goodwill, ending balance	730	668
Tools & Home Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	401	430
Acquisitions	0	0
Foreign currency translation and other	20	(29)
Goodwill, ending balance	$ 421	$ 401

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.

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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