Segment Information Geographic Segments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	$ 2,828.0	$ 2,733.9	$ 2,233.4
Operating Income (Loss)	526.1	532.8	210.2
Other operating credits and charges, net and gain (loss) on sales of and impairments of long-lived assets	(9.0)	(12.0)	(9.0)
General corporate expense, loss on early debt extinguishment, other income(expense) and interest, net	114.0	(131.0)	(148.0)
Income (loss) from continuing operations before income taxes, extraordinary items, noncontrolling interest	521.1	510.2	170.1
Provision for income taxes	122.3	119.1	19.8
Income (loss) from continuing operations	398.8	391.1	150.3
Disclosure on Geographic Areas, Long-Lived Assets in Entity's Country of Domicile	1,073.0	982.0	938.0
South America
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	160.8	155.3	136.9
Operating Income (Loss)	31.0	24.3	17.0
UNITED STATES
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	2,409.0	2,307.0	1,882.0
Operating Income (Loss)	475.0	462.0	239.0
Disclosure on Geographic Areas, Long-Lived Assets in Entity's Country of Domicile	540.0	529.0	516.0
CANADA
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	861.0	704.0	682.0
Operating Income (Loss)	138.0	167.0	71.0
Disclosure on Geographic Areas, Long-Lived Assets in Entity's Country of Domicile	449.0	380.0	365.0
South America
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	174.0	165.0	137.0
Operating Income (Loss)	31.0	24.0	17.0
Disclosure on Geographic Areas, Long-Lived Assets in Entity's Country of Domicile	84.0	73.0	57.0
Intersegment sales
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Sales	$ (616.0)	$ (442.0)	$ (468.0)

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