Supplementary Financial Statement Information - Property, Plant and Equipment (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 6,388.4us-gaap_PropertyPlantAndEquipmentGross	$ 5,871.9us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(4,175.2)	(3,991.8)
Property, plant and equipment, net	2,213.2us-gaap_PropertyPlantAndEquipmentNet	1,880.1us-gaap_PropertyPlantAndEquipmentNet
Capitalized interest on capital projects	2.7us-gaap_InterestCostsCapitalized	2.7us-gaap_InterestCostsCapitalized	2.5us-gaap_InterestCostsCapitalized
Asset retirement obligations	6.0us-gaap_AssetRetirementObligation	5.6us-gaap_AssetRetirementObligation
Land, land improvements and leaseholds [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	260.7	249.5
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	466.7	403.7
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	5,571.0	5,178.0
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 90.0	$ 40.7

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of interest capitalized during the period.

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-Glossary Allowance for Funds Used during Construction

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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