Supplementary Financial Statement Information - Property, Plant and Equipment (Details5) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 7,168.9	$ 6,969.2
Less accumulated depreciation	(5,237.0)	(5,057.6)
Property, plant and equipment, net	1,931.9	1,911.6
Capitalized interest on capital projects	3.1	1.6	$ 1.9
Asset retirement obligations	10.6	8.5
Land, land improvements and leaseholds [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	271.2	272.1
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	514.8	509.7
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	6,213.6	6,061.6
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 169.3	$ 125.8

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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