| **Fair Value Measurements (Fair Value Of Deferred Annuities, Structured Settlements And Other Items) (Details) - USD ($) $ in Millions** | Dec. 31, 2019 | Dec. 31, 2018 |
|------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | $ 982         | $ 927         |
| Deferred Annuities                                                                                                                       |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 770           | 742           |
| Structured Settlements                                                                                                                   |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 212           | 185           |
| Level 1                                                                                                                                  |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 0             | 0             |
| Level 1 | Deferred Annuities                                                                                                             |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 0             | 0             |
| Level 1 | Structured Settlements                                                                                                         |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 0             | 0             |
| Level 2                                                                                                                                  |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 212           | 185           |
| Level 2 | Deferred Annuities                                                                                                             |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 0             | 0             |
| Level 2 | Structured Settlements                                                                                                         |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 212           | 185           |
| Level 3                                                                                                                                  |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 770           | 742           |
| Level 3 | Deferred Annuities                                                                                                             |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | 770           | 742           |
| Level 3 | Structured Settlements                                                                                                         |          |          |
| **Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis**                                                       |          |          |
| Fair value of deferred annuities and structured settlements                                                                              | $ 0           | $ 0           |

| 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.
+ References
No definition available.
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| - Definition
Fair value portion of liability related to investment contracts for example, but not limited to, guaranteed investment contract or annuities.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 825 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6487514&loc=d3e32427-158581
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