| **Stockholders' Deficit - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions**                                            | 1 Months Ended | 9 Months Ended |             |             |        |        |
|-----------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|-------------|-------------|--------|--------|
||
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Preferred Stock, Shares Authorized                                                                                                      |           |           | 30,000,000  |        |   |   |
| Preferred Stock, Shares Issued                                                                                                          |           |           | 0           |        |   |   |
| Debt Instrument, Unamortized Discount                                                                                                   |           |           | $ 81        |        |   |   |
| Common stock, shares authorized                                                                                                         |           |           | 220,000,000 | 220,000,000 |   |   |
| Common stock, par value                                                                                                                 |           |           | $ 0.10      | $ 0.10      |   |   |
| Common Stock, Shares, Outstanding                                                                                                       |           |           | 81,500,000  | 81,400,000  |   |   |
| Preferred Stock, Par or Stated Value Per Share                                                                                          |           |           | $ 1         |        |   |   |
| Preference Stock [Member]                                                                                                               |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Preferred Stock, Shares Authorized                                                                                                      |           | 10,000,000     |        |        |   |   |
| Preferred Stock, Par or Stated Value Per Share                                                                                          |           | $ 1.00         | $ 1.00      |        |   |   |
| Convertible Junior Preference Stock Series D [Member]                                                                                   |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Preferred Stock, Par or Stated Value Per Share                                                                                          |           | 1.00           |        |        |   |   |
| Preferred Stock, Shares Outstanding                                                                                                     |           |           | 70,282      | 100,702     |   |   |
| Preferred Stock, Liquidation Preference Per Share                                                                                       |           | $ 25           |        |        |   |   |
| Convertible Preferred Stock, Shares Issued upon Conversion                                                                              |           | 0.3125         |        |        |   |   |
| Preferred Stock, Dividend Rate, Percentage                                                                                              |           | 120.00%        |        |        |   |   |
| Three Point Zero Percent Senior Subordinated Convertible Notes [Member]                                                                 |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Proceeds from Issuance of Warrants                                                                                                      |           | $ 87           |        |        |   |   |
| Three Point Zero Percent Senior Subordinated Convertible Notes [Member] | Call Option [Member] | Convertible Subordinated Debt [Member] |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Payments for Derivative Instrument, Investing Activities                                                                                | $ 125          |           |        |        |   |   |
| Four Point Five Zero Senior Subordinated Convertible Notes [Member] | Convertible Subordinated Debt [Member]                            |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Long-term Debt, Fair Value                                                                                                              |           |           |        |        |   | $ 177  |
| Debt Instrument, Unamortized Discount                                                                                                   |           |           |        |        |   | 1      |
| Debt Instrument, Convertible, Carrying Amount of Equity Component                                                                       |           |           |        |        |   | $ 22   |
| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member] | Convertible Subordinated Debt [Member]                  |           |           |        |        |   |   |
| **Class of Stock [Line Items]**                                                                                                         |           |           |        |        |   |   |
| Long-term Debt, Fair Value                                                                                                              |           |           |        |        | $ 367  |   |
| Debt Instrument, Unamortized Discount                                                                                                   |           |           |        |        | 1      |   |
| Debt Instrument, Convertible, Carrying Amount of Equity Component                                                                       |           |           |        |        | $ 44   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Face amount or stated value per share of common stock.
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| - Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares issued for each share of convertible preferred stock that is converted.
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| - Definition
The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.
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| - Definition
The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.
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| - Definition
The cash outflow for derivative instruments during the period, which are classified as investing activities, excluding those designated as hedging instruments.
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| - Definition
The percentage rate used to calculate dividend payments on preferred stock.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.
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| - Definition
Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.
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| - Definition
The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.
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| - Definition
Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.
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| - Definition
Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.
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| - Definition
The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).
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