| **Income Taxes (Details) (USD $)In Millions, unless otherwise specified**                                      | 3 Months Ended | 6 Months Ended |
|----------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Income Taxes [Line Items]**                                                                                  |           |           |
| Valuation Allowance, Deferred Tax Asset, Change in Amount                                                      | $ 181          |           |
| Income Taxes Percent Likelihood Of Being Realized Upon Settlement                                              | 50.00%         | 50.00%         |
| Liability for uncertain tax positions                                                                          | 13             | 13             |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate                                                 | 17             | 17             |
| Tax Adjustments, Settlements, and Unusual Provisions                                                           |           | 11             |
| Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound | 0              | 0              |
| Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound | $ 25           | $ 25           |

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| - Definition
Income Taxes Percent Likelihood Of Being Realized Upon Settlement
+ References
No definition available.
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| - Definition
The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reflects the effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings.
+ References
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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 total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.
+ References
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| - Definition
The amount of the change in the period in the valuation allowance for a specified deferred tax asset.
+ References
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