Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Details) $ in Millions	3 Months Ended
Dec. 31, 2021 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 18,335
Business Acquisitions	102
Business Divestitures	(5)
Currency Translation and Other	(46)
Ending Balance	18,386
Building Solutions North America
Goodwill [Roll Forward]
Beginning Balance	9,215
Business Acquisitions	20
Business Divestitures	0
Currency Translation and Other	1
Ending Balance	9,236
Building Solutions EMEA/LA
Goodwill [Roll Forward]
Beginning Balance	2,041
Business Acquisitions	27
Business Divestitures	(5)
Currency Translation and Other	(29)
Ending Balance	2,034
Building Solutions Asia Pacific
Goodwill [Roll Forward]
Beginning Balance	1,237
Business Acquisitions	45
Business Divestitures	0
Currency Translation and Other	4
Ending Balance	1,286
Global Products
Goodwill [Roll Forward]
Beginning Balance	5,842
Business Acquisitions	10
Business Divestitures	0
Currency Translation and Other	(22)
Ending Balance	$ 5,830

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/disclosureRef
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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