Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in unrecognized tax benefits
Beginning balance	$ 55.0us-gaap_UnrecognizedTaxBenefits	$ 48.7us-gaap_UnrecognizedTaxBenefits	$ 52.5us-gaap_UnrecognizedTaxBenefits
Additions for tax positions related to the current year	5.0	4.8	4.1
Additions for tax positions of prior years	2.5	2.8	0
Reductions for tax positions of prior years	(0.1)	0	(1.1)
Settlements	0	(0.3)	(3.4)
Expiration of statute of limitations	(0.1)	(1.0)	(3.4)
Ending balance	$ 62.3us-gaap_UnrecognizedTaxBenefits	$ 55.0us-gaap_UnrecognizedTaxBenefits	$ 48.7us-gaap_UnrecognizedTaxBenefits

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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