| **Income Taxes - Textual (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended |         | 1 Months Ended |        | 12 Months Ended |
|-------------------------------------------------------------------------------------|-----------------|---------|----------------|--------|-----------------|
||
| **Income Taxes (Textual) [Abstract]**                                               |            |    |           |   |            |   |   |   |   |   |
| Income Tax Benefit Resulting From Tax Settlement                                    |            |    | $ 18           |   | $ 115           |   |   |   |   |   |
| Increase Net Operating Loss Carryforward, Gross                                     |            |    |           |   | 283             |   |   |   |   |   |
| Net Reduction in Valuation Allowance                                                |            |    | 28             |   |            |   |   |   |   |   |
| Adjustment to Income Tax Expense, Prior Year Corrections                            |            |    | 7              |   |            |   |   |   |   |   |
| Net Operating Loss Carryforwards                                                    | 416.5           | 432.5   |           |   |            | 325.1 | 91.4 |   |   |   |
| Gross Operating Loss Carryforwards                                                  | 929.0           |    |           |   |            |   |   |   |   |   |
| Excess Tax Benefit from Share-based Compensation                                    | 8.6             |    |           |   |            |   |   |   |   |   |
| Deferred Tax Assets, Valuation Allowance, Decrease                                  | 9.1             | 10.5    | 62.4           |   |            |   |   | 21.0 | 34.0 | 7.0 |
| Valuation Allowance                                                                 | 30.7            | 39.8    |           |   |            |   |   |   |   |   |
| Gross Unrecognized Tax Benefits                                                     | 1.1             | 78.0    | 6.0            | 12.6   |            |   |   |   |   |   |
| Unrecognized Tax Benefits, Accrued Interest                                         | 0.3             | 0       | 0.1            | 1.1    |            |   |   |   |   |   |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate                      | 0.4             | 76.0    |           |   |            |   |   |   |   |   |
| Interest Income Included in Income Tax Expense                                      | (0.2)           | (0.7)   | (4.7)          |   |            |   |   |   |   |   |
| Total Accrued Interest (Expense) Income Related to Income Tax Matters               | $ 0.1           | $ (0.2) |           |   |            |   |   |   |   |   |

| X                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Income tax benefit resulting from settlements with taxing authorities (i.e. Federal, state, foreign) of income tax claims.
+ References
No definition available.
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| - Definition
Increase (decrease) in net operating loss carryforward on a gross basis due to a tax settlement.
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| - Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| - Definition
Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.
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| - Definition
The amount of estimated interest accrued as of the balance sheet date arising from income tax examinations.
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| - Definition
The amount of estimated interest recognized in the period arising from income tax examinations.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.
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| - Definition
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
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| - Definition
Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.
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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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| - Definition
The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.
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| - Definition
The amount of the change in the period in the valuation allowance for a specified deferred tax asset.
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