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Goodwill and Intangible Assets (Intangible Assets by Major Class) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | $ 63.9 | $ 63.1
Finite-lived intangible assets, accumulated amortization | (42.2) | (39.8)
Finite-lived intangible assets, net | 21.7 | 23.3
Patents and Licensing [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 18.2 | 17.8
Finite-lived intangible assets, accumulated amortization | (14.1) | (13.4)
Finite-lived intangible assets, net | 4.1 | 4.4
In-Process Research and Development (IPR&D) [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 3.3 | 3.3
Finite-lived intangible assets, accumulated amortization | (1.0) | (0.7)
Finite-lived intangible assets, net | 2.3 | 2.6
Trademarks [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 2.0 | 2.0
Finite-lived intangible assets, accumulated amortization | (1.7) | (1.6)
Finite-lived intangible assets, net | 0.3 | 0.4
Customer Relationships [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 29.3 | 29.3
Finite-lived intangible assets, accumulated amortization | (19.1) | (18.3)
Finite-lived intangible assets, net | 10.2 | 11.0
Customer Contracts [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 11.1 | 10.7
Finite-lived intangible assets, accumulated amortization | (6.3) | (5.8)
Finite-lived intangible assets, net | $ 4.8 | $ 4.9

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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