Valuation and Qualifying Accounts (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 24.6	$ 23.0	$ 18.9
Additions Charged to Costs and Expenses	6.0	5.0	7.9
Additions Charged to Other Accounts	1.2	0.1	0.1
Deductions	(6.1)	(3.5)	(3.9)
Ending balance	25.7	24.6	23.0
Valuation allowance for deferred tax assets
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	279.5	249.4	231.4
Additions Charged to Costs and Expenses	49.8	53.2	24.0
Additions Charged to Other Accounts	17.7	(0.5)	0
Deductions	(42.5)	(22.6)	(6.0)
Ending balance	$ 304.5	$ 279.5	$ 249.4

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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