Business Segments Information (Business Segments Financial Information) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 636	$ 568	$ 573
Capital expenditures	476	447	588
Operating Segments [Member] \| Automation Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	400	330	311
Capital expenditures	234	246	298
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	201	194	191
Capital expenditures	227	177	200
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	156	150	149
Capital expenditures	182	133	154
Operating Segments [Member] \| Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	45	44	42
Capital expenditures	45	44	46
Corporate, Non-Segment [Member] \| Corporate and other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	35	44	71
Capital expenditures	$ 15	$ 24	$ 90

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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- Definition

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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