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
Sales and operating results of reportable segments
Sales	$ 1,575.2	$ 1,649.5	$ 4,700.4	$ 4,841.7
Income before income taxes	284.6	274.0	848.6	795.2
Interest expense	(16.4)	(14.4)	(47.0)	(44.3)
Operating Segments [Member]
Sales and operating results of reportable segments
Income before income taxes	343.7	326.1	1,024.7	956.2
Architecture & Software [Member]
Sales and operating results of reportable segments
Sales	683.5	715.2	2,065.6	2,097.9
Income before income taxes	199.9	204.8	622.1	606.9
Control Products & Solutions [Member]
Sales and operating results of reportable segments
Sales	891.7	934.3	2,634.8	2,743.8
Income before income taxes	143.8	121.3	402.6	349.3
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(5.2)	(5.5)	(15.8)	(15.9)
Non-operating pension costs	(15.6)	(14.1)	(47.2)	(42.1)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate - net	(21.9)	(18.1)	(66.1)	(58.7)
Interest expense	$ (16.4)	$ (14.4)	$ (47.0)	$ (44.3)

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Non-operating pension costs consist of defined benefit plan interest cost, expected return on plan assets, amortization of actuarial gains and losses and the impacts of any plan curtailments or settlements. These costs are excluded from segment operating earnings.

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- Definition

Purchase accounting depreciation and amortization that is not allocated to the segments for the purposes of determining segment operating earnings.

+ References

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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 FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

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