Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Net sales	$ 4,928	$ 5,400	$ 9,641	$ 10,987
Earnings before income taxes	608	1,604	1,111	2,369
Gain on divestiture of business	0	932	0	932
Increase (decrease) in incentive stock compensation expense	46		67
Pretax separation costs	31	0	55	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	5,105	5,586	9,949	11,336
Earnings before income taxes	744	738	1,388	1,602
Operating Segments [Member] \| Process Management [Member]
Segment Reporting Information [Line Items]
Net sales	1,828	2,042	3,634	4,141
Earnings before income taxes	265	299	536	691
Operating Segments [Member] \| Industrial Automation [Member]
Segment Reporting Information [Line Items]
Net sales	870	1,034	1,678	2,186
Earnings before income taxes	116	144	211	308
Operating Segments [Member] \| Network Power [Member]
Segment Reporting Information [Line Items]
Net sales	1,018	1,063	2,069	2,182
Earnings before income taxes	83	34	167	113
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Net sales	995	982	1,782	1,882
Earnings before income taxes	188	170	297	296
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	394	465	786	945
Earnings before income taxes	92	91	177	194
Differences in accounting methods [Member]
Segment Reporting Information [Line Items]
Earnings before income taxes	58	53	113	111
Corporate and other [Member]
Segment Reporting Information [Line Items]
Earnings before income taxes	(148)	853	(298)	742
Intersegment Eliminations/Interest [Member]
Segment Reporting Information [Line Items]
Net sales	(177)	(186)	(308)	(349)
Earnings before income taxes	(46)	(40)	(92)	(86)
Intersegment Eliminations [Member] \| Industrial Automation [Member]
Segment Reporting Information [Line Items]
Net sales	$ (164)	$ (167)	$ (280)	$ (312)

Increase (decrease) in incentive stock compensation expense.

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- Definition

Separation Costs Related to Planned Portfolio Repositioning Actions

+ References

No definition available.

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51673353&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 10
-Article 5

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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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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