Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Sales and operating results of reportable segments
Sales	$ 1,599.2	$ 1,474.0	$ 4,643.8	$ 4,340.9
Income before income taxes	276.0	252.3	763.9	706.2
Interest expense	(19.1)	(18.1)	(56.7)	(53.1)
Operating Segments [Member]
Sales and operating results of reportable segments
Income before income taxes	337.0	311.0	949.6	884.4
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(5.6)	(4.7)	(16.8)	(13.9)
Non-operating pension costs	(19.8)	(18.9)	(59.4)	(56.7)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate - net	(16.5)	(17.0)	(52.8)	(54.5)
Interest expense	(19.1)	(18.1)	(56.7)	(53.1)
Architecture & Software [Member]
Sales and operating results of reportable segments
Sales	731.9	666.4	2,147.3	1,938.8
Income before income taxes	204.3	184.2	603.5	515.0
Control Products & Solutions [Member]
Sales and operating results of reportable segments
Sales	867.3	807.6	2,496.5	2,402.1
Income before income taxes	$ 132.7	$ 126.8	$ 346.1	$ 369.4

General Corporate - Net

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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.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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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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Amount of the cost of borrowed funds accounted for as interest 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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