Goodwill And Other Intangibles (Schedule Of Change In Carry Amount Of Goodwill By Business Segment) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 6,734	$ 6,536
Acquisitions	990	82
Foreign currency translation and other	(1)	116
Goodwill, ending balance	7,723	6,734
Automation Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	5,583	5,467
Acquisitions	967	23
Foreign currency translation and other	2	93
Goodwill, ending balance	6,552	5,583
Commercial & Residential Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	1,151	1,069
Acquisitions	23	59
Foreign currency translation and other	(3)	23
Goodwill, ending balance	1,171	1,151
Climate Technologies [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	730	668
Acquisitions	23	59
Foreign currency translation and other	0	3
Goodwill, ending balance	753	730
Tools & Home Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	421	401
Acquisitions	0	0
Foreign currency translation and other	(3)	20
Goodwill, ending balance	$ 418	$ 421

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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