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Acquisitions and Divestitures (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023
Business Acquisition [Line Items]
Cash paid for business acquisition	$ 2	$ 79
Goodwill	18,124		$ 17,936
Global Products
Business Acquisition [Line Items]
Goodwill	5,550		5,491
Building Solutions EMEA/LA
Business Acquisition [Line Items]
Goodwill	$ 1,961		$ 1,885
Individually Immaterial Acquisitions
Business Acquisition [Line Items]
Purchase price, net of cash acquired		105
Cash paid for business acquisition		79
Individually Immaterial Acquisitions \| Global Products
Business Acquisition [Line Items]
Goodwill		53
Individually Immaterial Acquisitions \| Building Solutions EMEA/LA
Business Acquisition [Line Items]
Goodwill		$ 2