| **Income Taxes (Narrative) (Details) - USD ($)**                               | 3 Months Ended | 12 Months Ended |
|--------------------------------------------------------------------------------|----------------|-----------------|
||
| **Income Tax Disclosure [Abstract]**                                           |           |            |   |   |
| Federal income taxes received from (paid to) Loews                             |           | $ 127,000,000   | $ 142,000,000 | $ 256,000,000 |
| Unrecognized tax benefits                                                      | $ 0            | 0               | 0 |   |
| Interest income (expense)                                                      |           | 0               | 0 | 0 |
| Income tax penalties expense                                                   |           | 0               | 0 | 0 |
| Accrued interest and penalties                                                 | 0              | 0               | 0 |   |
| Effective income tax rate reconciliation, change in enacted tax rate, amount   |           | (83,000,000)    |   |   |
| Net deferred tax asset remeasurement                                           | (83,000,000)   | (83,000,000)    | 0 | 0 |
| Deferred tax liability on undistributed income related to a foreign subsidiary | 2,000,000      | 2,000,000       |   |   |
| Undistributed earnings from a foreign subsidiary                               | 10,000,000     | 10,000,000      |   |   |
| Foreign tax expense (benefit) on income from continuing operations             |           | (1,000,000)     | (9,000,000) | (14,000,000) |
| Income (loss) from continuing foreign operations                               |           | 39,000,000      | 51,000,000 | $ 71,000,000 |
| Operating loss carryforwards                                                   | 0              | 0               |   |   |
| Valuation allowance                                                            | $ 0            | $ 0             | $ 0 |   |

| X                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Effective Income Tax Rate Reconciliation, Effect of Tax Cuts and Jobs Act of 2017, Amount
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Federal income taxes received from (paid to) Loews amount
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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 deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of foreign subsidiaries.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.
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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
The net amount of operating interest income (expense).
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| - Definition
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.
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| - Definition
Amount of unrecognized tax benefits.
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| - Definition
Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.
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| - Definition
Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.
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