Other after-tax adjustment for the impact of a court ruling on some uncertain tax positions.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Section S99

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-Subparagraph (SAB TOPIC 6.I)

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No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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Amount of decrease 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 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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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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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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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			9 Months Ended		12 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Taxes
U.S. corporate statutory income tax rate (as a percent)	35.00%		35.00%	35.00%	35.00%
Impact of court ruling on uncertain tax positions		$ (30.3)		$ (30.3)	$ (47.5)
Changes in Unrecognized Tax Benefits
Beginning balance, Unrecognized tax benefits		$ 172.4		172.4	$ 108.9	$ 108.9
Additions based on tax positions related to the current year				11.0		12.9
Additions for tax positions of prior years				46.7		62.5
Reductions for tax positions related to the current year				(7.1)		(8.4)
Reductions for tax positions of prior years				(3.5)		(0.2)
Settlements						(3.3)
Ending balance, Unrecognized tax benefits	$ 219.5			219.5		172.4
Amount of unrecognized tax benefits that would reduce the effective income tax rate, if recognized	81.0			81.0
Accumulated pre-tax interest and penalties related to unrecognized tax benefits	$ 137.4			$ 137.4		$ 100.4