| **Income Taxes - Textual (Details) (USD $)**                                                                                            | 3 Months Ended | 9 Months Ended |               | 1 Months Ended |              |
|-----------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|---------------|----------------|--------------|
||
| **Income Tax Contingency [Line Items]**                                                                                                 |           |           |          |           |         |   |   |
| Income Tax Benefit Associated with Tax Settlements                                                                                      |           |           |          |           |         | $ 115,000,000 |   |
| Increase (Decrease) Net Operating Loss Carryforward, Gross                                                                              |           |           |          |           |         | 283,000,000 |   |
| Provision for income tax (benefit) expense                                                                                              | 35,200,000     | 28,100,000     | (17,800,000)  | 84,100,000     |         |   |   |
| Income Tax Reconciliation, Change in Deferred Tax Assets Valuation Allowance                                                            |           | (1,000,000)    | (4,000,000)   | (1,000,000)    |         |   |   |
| Net Deferred Tax Assets, Total                                                                                                          | 550,100,000    |           | 550,100,000   |           |         |   |   |
| Deferred Tax Assets, Valuation Allowance                                                                                                | 35,600,000     |           | 35,600,000    |           |         |   |   |
| Deferred Tax Assets, Operating Loss Carryforwards                                                                                       |           |           |          |           |         |   | 358,300,000 |
| Operating Loss Carryforwards                                                                                                            | 1,000,000,000  |           | 1,000,000,000 |           |         |   |   |
| Excess Tax Benefits From Share-Based Compensation                                                                                       | 6,200,000      |           | 6,200,000     |           |         |   |   |
| Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations And Settlements With Taxing Authorities |           | (1,000,000)    |          | (1,000,000)    |         |   |   |
| Gross Unrecognized Tax Benefits                                                                                                         | $ 3,000,000    |           | $ 3,000,000   |           | $ 78,000,000 |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
No definition available.
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| 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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| X                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Increase (decrease) in net operating loss carryforward on a gross basis due to a tax settlement.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations and settlements with taxing authorities.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
+ References
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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.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.
+ References
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