Nature of Operations (Reconciliation of Unallocated Corporate Segment Operating Loss) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Corporate expenses	$ (225.2)	$ (267.7)	$ (250.1)
Separation costs	(34.5)	(34.3)
Segment operating income (loss)	184.6	140.5	198.1
Unallocated Corporate Segment [Member]
Segment Reporting Information [Line Items]
Corporate expenses	(4.3)	(90.0)	(66.6)
Separation costs	(34.5)	(34.3)
Segment operating income (loss)	$ (38.8)	$ (124.3)	$ (66.6)

The net result for the period of deducting operating expenses from operating revenues.

No definition available.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

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-Publisher FASB
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-Name Accounting Standards Codification
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-Section S99
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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