Business Segments Information (Financial Information) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 969	$ 854	$ 822
Capital expenditures	581	538	594
Operating Segments [Member] \| Automation Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	632	557	535
Capital expenditures	325	308	297
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	267	261	247
Capital expenditures	237	216	281
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	191	184	176
Capital expenditures	143	158	222
Operating Segments [Member] \| Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	76	77	71
Capital expenditures	94	58	59
Corporate, Non-Segment [Member] \| Corporate and other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	70	36	40
Capital expenditures	$ 19	$ 14	$ 16

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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