Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Sales and operating results of reportable segments
Sales	$ 1,554.3	$ 1,440.3	$ 3,044.6	$ 2,866.9
Income before income taxes	230.3	217.0	487.9	453.9
Interest expense	(18.9)	(17.6)	(37.6)	(35.0)
Operating Segments [Member]
Sales and operating results of reportable segments
Income before income taxes	296.0	277.5	612.6	573.4
Segment Reconciling Items [Member]
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(5.6)	(4.5)	(11.2)	(9.2)
Non-operating pension costs	(19.8)	(18.9)	(39.6)	(37.8)
Corporate, Non-Segment [Member]
Sales and operating results of reportable segments
General corporate - net	(21.4)	(19.5)	(36.3)	(37.5)
Interest expense	(18.9)	(17.6)	(37.6)	(35.0)
Architecture & Software [Member]
Sales and operating results of reportable segments
Sales	719.0	629.5	1,415.4	1,272.4
Income before income taxes	190.6	154.6	399.2	330.8
Control Products & Solutions [Member]
Sales and operating results of reportable segments
Sales	835.3	810.8	1,629.2	1,594.5
Income before income taxes	$ 105.4	$ 122.9	$ 213.4	$ 242.6

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.

+ 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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-Name Accounting Standards Codification
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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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- 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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