Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Sales and operating results of reportable segments
Sales	$ 1,490.3	$ 1,426.6
Income before income taxes	257.6	236.9
Interest expense	(18.7)	(17.4)
Operating Segments [Member]
Sales and operating results of reportable segments
Income before income taxes	316.6	295.9
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(5.6)	(4.7)
Non-operating pension costs	(19.8)	(18.9)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate - net	(14.9)	(18.0)
Interest expense	(18.7)	(17.4)
Architecture & Software [Member]
Sales and operating results of reportable segments
Sales	696.4	642.9
Income before income taxes	208.6	176.2
Control Products & Solutions [Member]
Sales and operating results of reportable segments
Sales	793.9	783.7
Income before income taxes	$ 108.0	$ 119.7

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.

+ References

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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.

+ 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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-Name Accounting Standards Codification
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-Section S99
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 20
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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