Debt And Credit Arrangements Scheduled Annual Maturities (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	[1]	$ 60.9
Long-term Debt, Maturities, Repayments of Principal in Year Two		4.1
Long-term Debt, Maturities, Repayments of Principal in Year Five		239.0
Long-term Debt, Maturities, Repayments of Principal after Year Five		258.8
Long Term Debt Maturities Total Repayments Due		562.8
Interest Paid		9.3	$ 5.6	$ 5.1
Convertible Notes, Due 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months		57.1
Foreign Facilities [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months		$ 3.8

[1] (1) Includes the $57.1 fully accreted amount of our 2018 Notes and $3.8 current maturities related to foreign facilities.