| **Income Taxes - Textual (Details) (USD $)In Millions, unless otherwise specified**     | 3 Months Ended | 12 Months Ended |        | 1 Months Ended |        | 1 Months Ended |
|-----------------------------------------------------------------------------------------|----------------|-----------------|--------|----------------|--------|----------------|
||
| **Income Tax Contingency [Line Items]**                                                 |           |            |   |           |   |           |   |
| Provision for income tax expense (benefit)                                              | $ 33.5         | $ 29.1          |   |           |   |           |   |
| Estimated Effective Blended Federal and State Income Tax Rate                           | 39.00%         |            |   |           |   |           |   |
| Operating Loss Carryforwards, Expiration Dates                                          |           |            | 2031   |           |   |           |   |
| Net Deferred Tax Assets, Total                                                          | 497.3          |            |   |           |   |           |   |
| Deferred Tax Assets, Valuation Allowance                                                | 39.8           |            |   |           |   |           |   |
| Deferred Tax Assets, Operating Loss Carryforwards                                       |           |            |   |           |   | 317.2          |   |
| Operating Loss Carryforwards                                                            | 906.2          |            |   |           |   |           |   |
| Excess Tax Benefits From Share-Based Compensation                                       | 6.5            |            |   |           |   |           |   |
| Income Tax Benefit Associated with Tax Settlements                                      |           |            |   |           |   |           | 91 |
| Increase (Decrease) Net Operating Loss Carryforward, Gross                              |           |            |   |           |   |           | 260 |
| Gross Unrecognized Tax Benefits                                                         | 116.4          |            |   | 78.0           |   |           |   |
| Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities |           |            |   |           | $ 112  |           |   |

| X                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The estimated blended federal and state statutory income tax rates currently in effect.
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| - Definition
As of the balance sheet date, the amount that would reduce the entity's income taxes that arise when compensation cost (from non-qualified equity-based compensation) recognized on the entity's tax return exceeds compensation cost from equity-based compensation recognized in financial statements.
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| X                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Income tax benefit resulting from settlements with taxing authorities (i.e. Federal, state, foreign) of income tax claims.
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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 after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.
+ References
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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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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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 sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The expiration date of each operating loss carryforward included in total operating loss carryforwards, or the applicable range of such expiration dates.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.
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