Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Goodwill
Beginning Balance	$ 1,050.6	$ 1,023.0
Acquisition of businesses	14.9	35.7
Translation and other	(36.7)	(8.1)
Ending Balance	1,028.8	1,050.6
Architecture and Software [Member]
Goodwill
Beginning Balance	395.6	387.8
Acquisition of businesses	0.0	7.7
Translation and other	(7.6)	0.1
Ending Balance	388.0	395.6
Control Products and Solutions [Member]
Goodwill
Beginning Balance	655.0	635.2
Acquisition of businesses	14.9	28.0
Translation and other	(29.1)	(8.2)
Ending Balance	$ 640.8	$ 655.0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

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