Goodwill and Other Intangible Assets (Details) $ in Millions	9 Months Ended
Jun. 30, 2017 USD ($)
Goodwill
Balance as of September 30, 2016	$ 1,073.9
Acquisition of business	0.8
Translation	(5.0)
Balance as of June 30, 2017	1,069.7
Architecture & Software [Member]
Goodwill
Balance as of September 30, 2016	414.5
Acquisition of business	0.0
Translation	(1.2)
Balance as of June 30, 2017	413.3
Control Products & Solutions [Member]
Goodwill
Balance as of September 30, 2016	659.4
Acquisition of business	0.8
Translation	(3.8)
Balance as of June 30, 2017	$ 656.4

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
-Subparagraph (a)
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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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.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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