Other Expense Other Items (Textuals) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Feb. 17, 2016
Summary of Investment Holdings [Line Items]
Pension settlement charge	$ 0.0	$ 0.0	$ 50.4
Annuity purchase			47.0
Lump sum payments			3.4
Pension curtailment gain	0.0	2.1	0.0
Executive retirement and related costs	0.0	0.0	10.9
Share-based compensation, new LTIP award			2.4
Share-based compensation, modified awards			8.0
Other retirement related costs			0.5
Venezuela currency devaluation	0.0	2.7	0.0
Venezuela deconsolidation	$ (11.1)	$ 0.0	$ 0.0
VENEZUELA
Summary of Investment Holdings [Line Items]
Foreign currency exchange rate, remeasurement			6.3	10.0

The amount of the gain (loss) recognized by the parent and included in its attributable portion of net income for the period due to deconsolidation of a subsidiary or derecognition of a group of assets. The gain (loss) recognized and included in the net income attributable to the parent for the period is generally computed as the difference between: (a) the aggregate of: (1) the fair value of any consideration received; (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary was deconsolidated; and (3) the carrying amount of any noncontrolling interest in the former subsidiary (including any accumulated other comprehensive income attributable to the noncontrolling interest) at the date the subsidiary was deconsolidated and (b) the carrying amount of the former subsidiary's assets and liabilities.

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