Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Income Taxes [Abstract]
Reduction in reserves for uncertain tax positions		$ 9.6
Interest for uncertain tax positions		4.7
Reduction in income tax provision		10.9
Excess tax benefits related to stock-based awards, which increased the cash flow from financing activities		3.4
Effective income tax rate	38.30%	24.70%	39.00%	34.10%
Reduction in its income tax provision resulting from the resolution of the tax matters		$ 10.9		$ 10.9

Reduction in its income tax provision resulting from the resolution of the tax matters.

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Adjustment to additional paid in capital related to the net effect of excess tax benefits and tax deficiencies associated with an equity-based compensation plan other than an employee stock ownership plan (ESOP).

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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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The increase (decrease) during the reporting period in the amounts payable to taxing authorities for taxes that are based on the reporting entity's earnings, net of amounts receivable from taxing authorities for refunds of overpayments or recoveries of income taxes, and in deferred and other tax liabilities and assets.

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This element represents 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.

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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