Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Net sales	$ 5,503	$ 6,312	$ 16,490	$ 17,730
Earnings before income taxes	796	1,072	3,165	2,532
Eliminations/Interest	(40)	(46)	(126)	(147)
Increase (decrease) in incentive stock compensation expense			(56)
Gain on sale of business	0	0	932	0
Increase in income from equity method investment loss in prior year			34
Increase (decrease) in pretax charitable contributions			(28)
Increase (decrease) in inventory costs (purchase accounting)			20
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	5,704	6,526	17,040	18,283
Earnings before income taxes	886	1,152	2,488	2,928
Operating Segments [Member] \| Process Management [Member]
Segment Reporting Information [Line Items]
Net sales	2,084	2,317	6,225	6,466
Earnings before income taxes	373	473	1,064	1,229
Operating Segments [Member] \| Industrial Automation [Member]
Segment Reporting Information [Line Items]
Net sales	990	1,289	3,176	3,670
Earnings before income taxes	156	214	464	563
Operating Segments [Member] \| Network Power [Member]
Segment Reporting Information [Line Items]
Net sales	1,028	1,237	3,210	3,711
Earnings before income taxes	37	107	150	286
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Net sales	1,125	1,191	3,007	3,018
Earnings before income taxes	222	250	518	543
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	477	492	1,422	1,418
Earnings before income taxes	98	108	292	307
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Differences in accounting methods	54	63	165	180
Corporate and other	(104)	(97)	638	(429)
Eliminations/Interest	(40)	(46)	(126)	(147)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(201)	(214)	(550)	(553)
Intersegment Eliminations [Member] \| Industrial Automation [Member]
Segment Reporting Information [Line Items]
Net sales	$ (184)	$ (194)	$ (496)	$ (492)

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Differences in accounting methods

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- Definition

Increase (decrease) in incentive stock compensation expense.

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Increase (decrease) in inventory costs (purchase accounting) versus prior period.

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Increase (decrease) in pretax charitable contributions

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- Definition

Increase (decrease) in income (loss) from equity method investment

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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.

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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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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The net amount of nonoperating interest income (expense).

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-03.1)

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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.

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