Segment Information - Textuals (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	$ 518.8	$ 521.7
Revenue	2,745.1	2,585.3	$ 2,405.4
Gain (Loss) on Disposition of Property Plant Equipment	$ 40.7	0.9	0.9
Number of reportable segments \| Segment	3
Total segment results
Segment Reporting Information [Line Items]
Revenue	$ 2,747.8	2,588.8	2,409.8
Gain (Loss) on Disposition of Property Plant Equipment	2.2	0.9	0.3
United States
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	159.7	168.3
Revenue	887.0	853.6	900.3
Germany
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	101.0	102.9
Revenue	$ 412.5	$ 389.3	$ 324.4

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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