Goodwill and Other Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Mar. 31, 2015
Goodwill
Balance as of September 30, 2014	$ 1,050.6us-gaap_Goodwill
Acquisition of business	14.9us-gaap_GoodwillAcquiredDuringPeriod
Translation and other	(36.9)
Balance as of March 31, 2015	1,028.6us-gaap_Goodwill
Finite-lived Intangible Assets Acquired	5.4
Architecture & Software [Member]
Goodwill
Balance as of September 30, 2014	395.6
Acquisition of business	0
Translation and other	(8.5)
Balance as of March 31, 2015	387.1
Control Products & Solutions [Member]
Goodwill
Balance as of September 30, 2014	655.0
Acquisition of business	14.9
Translation and other	(28.4)
Balance as of March 31, 2015	$ 641.5

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

No definition available.

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- Definition

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.

+ References

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

-Subparagraph (a)

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

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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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

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

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