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Other Operating Income (Expense) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effect of Fourth Quarter Events [Line Items]
Foreign currency transaction losses					$ (13.9)	$ (9.2)	$ 1.4
Foreign currency derivative instrument gains (losses)					7.7	0.8	(2.4)
Gains (losses) on sale of property and equity investment					4.0	9.2	(1.3)
Impairment losses					(6.5)	(3.4)	(20.6)
Share in earnings (losses) of equity affiliates					1.9	0.4	(1.5)
Royalty Income					4.5	1.9	2.6
Gains (losses) on business acquisitions and dispositions					0.0	0.6	0.1
Other					0.6	3.0	1.6
Other operating income (expense)					(1.7)	3.3	(20.1)
ARGENTINA \| Argentina, Pesos
Effect of Fourth Quarter Events [Line Items]
Currency remeasurement gain (loss)	$ (8.1)				(6.2)
Venezuela \| Venezuelan bolívar fuerte
Effect of Fourth Quarter Events [Line Items]
Currency remeasurement gain (loss)			$ (8.1)	$ 2.2		(9.1)	(4.8)
Mexico
Effect of Fourth Quarter Events [Line Items]
Gains (losses) on sale of property and equity investment		$ 7.8			$ 3.0	$ 8.4
Reorganization and Restructuring 2016
Effect of Fourth Quarter Events [Line Items]
Impairment losses							$ (13.6)