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Goodwill and Intangible Assets (Intangible Assets by Major Class) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | $ 65.2 | $ 63.9
Finite-lived intangible assets, accumulated amortization | (44.9) | (42.2)
Finite-lived intangible assets, net | 20.3 | 21.7
Patents and Licensing [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 19.6 | 18.2
Finite-lived intangible assets, accumulated amortization | (15.1) | (14.1)
Finite-lived intangible assets, net | 4.5 | 4.1
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 | (1.2) | (1.0)
Finite-lived intangible assets, net | 2.1 | 2.3
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 | (1.8) | (1.7)
Finite-lived intangible assets, net | 0.2 | 0.3
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 | (20.0) | (19.1)
Finite-lived intangible assets, net | 9.3 | 10.2
Customer Contracts [Member] |  |
Schedule of Intangible Assets by Major Class [Line Items] |  |
Finite-lived intangible assets, gross | 11.0 | 11.1
Finite-lived intangible assets, accumulated amortization | (6.8) | (6.3)
Finite-lived intangible assets, net | $ 4.2 | $ 4.8

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