| **Earnings Per Common Share - Textual (Details) (USD $)In Millions, except Share data, unless otherwise specified** | 1 Months Ended | 3 Months Ended | 12 Months Ended |           |            | 1 Months Ended | 3 Months Ended | 12 Months Ended |        | 0 Months Ended | 1 Months Ended | 0 Months Ended |           |
|---------------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|-----------|------------|----------------|----------------|-----------------|--------|----------------|----------------|----------------|-----------|
||
| **Earnings Per Common Share (Textual) [Abstract]**                                                                  |           |           |            |      |       |           |           |            |   |           |           |           |      |   |   |   |   |   |   |   |
| Antidilutive Securities Excluded from Computation of Earnings Per Share                                             |           |           |            | 100,000   | 1,800,000  |           |           |            |   |           |           |           |      |   |   |   |   |   |   |   |
| Stock Repurchase Program, Authorized Amount                                                                         |           |           |            |      |       |           |           |            |   | $ 200          | $ 350          | $ 125          |      |   |   |   |   | $ 250 |   |   |
| Repurchase of common stock through tender offer, Shares                                                             |           |           |            | 9,100,000 |       |           |           |            |   |           |           |           | 9,100,000 |   |   |   |   |   |   |   |
| Treasury Stock Acquired, Average Cost Per Share                                                                     |           |           |            |      |       |           |           |            |   |           |           |           | $ 25.50   |   |   |   |   |   |   |   |
| Repurchase of Common Stock                                                                                          |           |           |            |      |       |           |           |            |   |           |           |           | 234.1     |   |   |   |   |   |   |   |
| Common Stock, Dividends, Per Share, Declared                                                                        | $ 0.18         | $ 0.18         | $ 0.18          | $ 0.36    | $ 0.00     | $ 0.00         |           |            |   |           |           |           |      |   |   |   |   |   |   |   |
| Dividends Payable, Current                                                                                          |           |           |            |      |       |           |           |            |   |           |           |           |      | 15.8 |   |   |   |   |   |   |
| Debt Instrument, Interest Rate, Stated Percentage                                                                   |           |           |            |      |       |           |           |            | 3.25%  |           |           |           |      |   |   |   |   |   |   |   |
| Class of Warrant or Right, Outstanding                                                                              |           |           | 2,900,000       | 2,900,000 | 10,000,000 |           |           | 10              |   |           |           |           |      |   |   | 0 |   |   |   |   |
| Stock Warrants Issued, Potential Number of Common Stock Shares                                                      |           |           |            |      |       |           |           |            |   |           |           |           |      |   | 2 |   |   |   |   |   |
| Stock Warrants Issued, Exercise Price                                                                               |           |           | $ 32.50         | $ 32.50   | $ 32.50    |           | $ 41.40        |            |   |           |           |           |      |   | $ 32.50 | $ 32.16 |   |   |   | $ 32.16 |
| Common Stock, Dividends, Per Share, Cash Paid                                                                       |           |           |            |      |       |           |           |            |   |           |           |           |      |   |   |   | $ 0.18 |   |   |   |
| Stock Warrants Issued, Exercise Rate                                                                                |           |           |            |      |       |           |           |            |   |           |           |           |      |   |   |   |   |   |   | 0.2021 |
| Stock warrants exercised, Shares                                                                                    |           |           |            |      |       |           |           |            |   |           |           |           |      | 500,000 |   |   |   |   | 200,000 |   |
| Proceeds from exercising stock warrants                                                                             |           |           |            | $ 15.3    | $ 0        | $ 0            |           |            |   |           |           |           |      |   |   | $ 6.3 |   |   |   |   |
| Common Stock Shares Issued Under Consolidated Securities Action Settlement                                          |           |           |            |      |       |           | 5,000,000      |            |   |           |           |           |      |   |   |   |   |   |   |   |
| Common Stock Warrants Issued Under Consolidated Securities Action Settlement                                        |           |           |            |      |       |           | 8,200,000      |            |   |           |           |           |      |   |   |   |   |   |   |   |
| Stock Warrants Issued, Term                                                                                         |           |           |            |      |       |           | 7              |            |   |           |           |           |      |   |   |   |   |   |   |   |

| X                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Exercise price per share of warrants outstanding.
+ References
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| X                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Exercise rate per share of warrants or rights outstanding.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares of common stock issued during the period in full satisfaction of the Company's obligation to do so under the Consolidated Securities Action Settlement.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of common stock warrants issued during the period in full satisfaction of the Company's obligation to do so under the Consolidated Securities Action Settlement.
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| X                                                                                                                                                                 |
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| X                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Cost of common stock repurchased during the period and currently held in treasury.
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| X                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The stock warrants exercises resulted in the issuance of shares of common stock.
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| X                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The contractual term of each class of warrants or rights outstanding.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of warrants or rights outstanding.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate dividends paid during the period for each share of common stock outstanding.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate dividends declared during the period for each share of common stock outstanding.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).
+ References
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| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash inflow associated with the amount received from holders exercising their stock warrants.
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| X                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of a stock repurchase plan authorized by an entity's Board of Directors.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total cost of shares repurchased divided by the total number of shares repurchased.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares that have been repurchased during the period and are being held in treasury.
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