Income Taxes [Abstract]

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Glossary Income Tax Expense (or Benefit)
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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.

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Taxes [Abstract]
Effective tax rate			30.80%	32.60%
Accounting Changes [Line Items]
Income tax benefit	$ (166.7)	$ (167.9)	$ (274.7)	$ (283.4)
Unrecognized tax benefits	110.0		110.0
Unrecognized tax benefits that would impact effective tax rate	$ 72.3		72.3
Accounting Standards Update 2016-09 [Member]
Accounting Changes [Line Items]
Income tax benefit			$ 14.8