| **Life Policy And Investment Contract Reservess (Reserve In Addition To The Account Balance Based On Expected No-Lapse Guarantee Benefits And Expected Policy Assessments) (Details) - USD ($) $ in Millions** | Dec. 31, 2019 | Dec. 31, 2018 |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | $ 2,835       | $ 2,779       |
| Life Policy Reserves                                                                                                                                                                                           |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 1,276         | 1,197         |
| Life Policy Reserves | Ordinary/Traditional Life                                                                                                                                                               |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 1,226         | 1,149         |
| Life Policy Reserves | Other Life Policy Reserves                                                                                                                                                              |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 50            | 48            |
| Investment contract reserves                                                                                                                                                                                   |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 1,559         | 1,582         |
| Investment contract reserves | Deferred Annuities                                                                                                                                                              |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 760           | 787           |
| Investment contract reserves | Universal Life                                                                                                                                                                  |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 640           | 632           |
| Investment contract reserves | Structured Settlements                                                                                                                                                          |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | 151           | 156           |
| Investment contract reserves | Other Investment Contract Reserves                                                                                                                                              |          |          |
| **Liability for Future Policy Benefit, by Product Segment**                                                                                                                                                    |          |          |
| Life policy and investment contract reserves                                                                                                                                                                   | $ 8           | $ 7           |

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| - 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
Amount of accrued obligation to policyholders that relates to insured events under long-term life insurance contracts.
+ References
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| X                                                                                                                                                 |
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