Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 180.1	$ 167.0
Goodwill, Acquired During Period	5.0
Currency translation adjustment	(2.5)	13.1
Goodwill, ending balance	182.6	180.1
Materials
Goodwill [Roll Forward]
Goodwill, beginning balance	162.6	150.6
Goodwill, Acquired During Period	5.0
Currency translation adjustment	(2.3)	12.0
Goodwill, ending balance	165.3	162.6
Delivery Systems and Services
Goodwill [Roll Forward]
Goodwill, beginning balance	17.5	16.4
Goodwill, Acquired During Period	0.0
Currency translation adjustment	(0.2)	1.1
Goodwill, ending balance	$ 17.3	$ 17.5

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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- 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

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- Definition

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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- Definition

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

+ References

No definition available.

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