| **Stockholders' Deficit (Details) (USD $)In Millions, except Share data, unless otherwise specified** | 3 Months Ended | 6 Months Ended | 1 Months Ended |        | 1 Months Ended |           | 1 Months Ended | 3 Months Ended |
|-------------------------------------------------------------------------------------------------------|----------------|----------------|----------------|--------|----------------|-----------|----------------|----------------|
||
| **Class of Stock [Line Items]**                                                                       |           |           |           |   |           |      |           |           |   |   |   |   |   |   |   |   |   |   |
| Stock Issued During Period, Shares, New Issues                                                        |           |           |           |   |           |      |           |           |   |   |   |   |   |   |   |   | 763,534 | 10,666,666 |
| Price per share (in dollars per share)                                                                |           |           |           |   |           |      |           |           |   |   |   |   |   |   |   |   | $ 18.75 | $ 18.75 |
| Proceeds from Issuance of Common Stock                                                                | $ 14           | $ 192          | $ 14           | $ 0    |           |      |           |           |   |   |   |   |   |   |   |   |   |   |
| Stock Repurchase Program, Authorized Amount                                                           |           |           |           |   | 175            |      | 100            |           |   |   |   |   |   | 75 |   |   |   |   |
| Treasury Stock, Shares, Acquired                                                                      |           |           |           |   |           | 2,542,609 |           |           |   | 2,380,952 |   |   | 1,905,600 |   |   |   |   |   |
| Payments for Repurchase of Common Stock                                                               |           |           | 0              | 75     |           |      |           |           |   |   |   |   |   |   | 5 | 70 |   |   |
| Accelerated Share Repurchases, Settlement Payment or Receipt                                          |           |           |           |   |           |      |           |           | 80 |   | 20 |   |   |   |   |   |   |   |
| Accelerated Share Repurchases, Initial Price Paid Per Share                                           |           |           |           |   |           |      |           | $ 33.60        |   |   |   |   |   |   |   |   |   |   |
| Stock Repurchase Program, Remaining Authorized Repurchase Amount                                      |           |           |           |   |           |      | $ 20           |           |   |   |   |   |   |   |   |   |   |   |
| Treasury Stock, Additional Shares Acquired                                                            |           |           |           |   |           |      |           |           |   |   |   | 161,657 |   |   |   |   |   |   |

| X                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Treasury Stock, Additional Shares Acquired
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The price paid per share to immediately purchase the targeted number of shares on the date of executing the accelerated share repurchase agreement.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of cash payment to or cash receipt from the bank; or the stock issuance to or stock received from the bank in the settlement of the accelerated share repurchase agreement.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow to reacquire common stock during the period.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash inflow from the additional capital contribution to the entity.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Price of a single share of a number of saleable stocks of a company.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of new stock issued during the period.
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| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount authorized by an entity's Board of Directors under a stock repurchase plan.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.
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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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