Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Liability for unrecognized tax benefits	$ 58.9		$ 58.9		$ 112.3
Unrecognized tax benefits that would affect income tax expense	46.3		46.3
Interest and penalties share in unrecognized tax benefits			17.8
Effective tax rate on net income from continuing operations	16.40%	25.70%	13.60%	26.10%
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	3		3
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	$ 10		$ 10

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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-Name Regulation S-X (SX)

-Number 210

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-Publisher FASB

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The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

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This element represents the total of interest expense recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties in the period in which the entity claims or expects to claim a tax position, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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