Joint Ventures (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) joint_venture	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Summarized Financial Information, Revenue	$ 105.0	$ 107.5	$ 122.0
Equity Method Investment, Summarized Financial Information, Current Assets	112.4	118.6
Equity Method Investments	68.5	63.8
Equity Method Investment, Summarized Financial Information, Noncurrent Assets	205.3	201.7
Equity Method Investment, Summarized Financial Information, Current Liabilities	64.8	69.6
Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities	114.7	122.0
Equity Method Investment Summarized Financial Information, Equity	138.2	128.7
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss)	28.8	36.5	42.7
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	$ 4.9	9.5	13.2
China [Member]
Schedule of Equity Method Investments [Line Items]
Number of Joint Ventures \| joint_venture	2
Equity Method Investment, Ownership Percentage	50.00%
Management Fees Revenue	$ 2.1	$ 2.0	$ 2.9

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