| **Income Taxes - Narrative (Details) - USD ($)**                                   | 1 Months Ended | 3 Months Ended | 9 Months Ended |
|------------------------------------------------------------------------------------|----------------|----------------|----------------|
||
| **Operating Loss Carryforwards [Line Items]**                                      |           |           |           |   |   |   |   |
| Unusual or Infrequent Item, or Both, Tax Effect                                    | $ 38,000,000   |           |           |   |   |   |   |
| Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount       |           |           |           | $ 0.21 | $ 0.35 |   |   |
| Deferred Tax Assets, Valuation Allowance                                           |           |           | $ 983,000,000  |   |   | $ 983,000,000 |   |
| Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount |           | $ 147,000,000  |           |   |   |   |   |
| Income Taxes Percent Likelihood Of Being Realized Upon Settlement                  |           |           | 50.00%         |   |   | 50.00% |   |
| Income Tax Expense (Benefit)                                                       |           |           | $ 29,000,000   | $ 3,000,000 |   | $ 9,000,000 | $ 25,000,000 |
| Unrecognized Tax Benefits                                                          |           |           | $ 21,000,000   |   |   | 21,000,000 |   |
| Interest and Penalties from Uncertain Tax Positions, Income Tax Expense            |           |           |           |   |   | 1,000,000 |   |
| Other Comprehensive Income (Loss) [Member]                                         |           |           |           |   |   |   |   |
| **Operating Loss Carryforwards [Line Items]**                                      |           |           |           |   |   |   |   |
| Income Tax Expense (Benefit)                                                       |           |           |           |   |   | $ (9,000,000) |   |

| X                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Income Taxes Percent Likelihood Of Being Realized Upon Settlement
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Interest and Penalties from Uncertain Tax Positions, Income Tax Expense
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| - 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.
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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 income tax rates.
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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 repatriation of foreign earnings.
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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
Amount of unrecognized tax benefits.
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| - Definition
Amount of tax related to an event or transaction that is unusual in nature or infrequent in occurrence, or both.
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