| **Shareholders' Equity And Dividend Restrictions (Change In AOCI Includes Changes In Unrealized Gains And Losses On Investments And Pension Obligations) (Details) - USD ($) $ in Millions** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| Pension obligations OCI                                                                                                                                                                      | $ (6)           | $ 9 | $ 68 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (614)           |   |   |
| AOCI, balance at the end of the period                                                                                                                                                       | (435)           | (614) |   |
| Accumulated Net Unrealized Investment Gain (Loss)                                                                                                                                            |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (847)           | 792 | 1,026 |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 255             | (1,642) | (204) |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 22              | 3 | (30) |
| OCI                                                                                                                                                                                          | 277             | (1,639) | (234) |
| AOCI, balance at the end of the period                                                                                                                                                       | (570)           | (847) | 792 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (182)           | 165 | 215 |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 55              | (347) | (44) |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 4               | 0 | (6) |
| OCI                                                                                                                                                                                          | 59              | (347) | (50) |
| AOCI, balance at the end of the period                                                                                                                                                       | (123)           | (182) | 165 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (665)           | 627 | 811 |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 200             | (1,295) | (160) |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 18              | 3 | (24) |
| OCI                                                                                                                                                                                          | 218             | (1,292) | (184) |
| AOCI, balance at the end of the period                                                                                                                                                       | (447)           | (665) | 627 |
| Accumulated Defined Benefit Plans Adjustment                                                                                                                                                 |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 36              | 27 | (41) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 2               | 12 | 62 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | (8)             | (3) | 6 |
| OCI                                                                                                                                                                                          | (6)             | 9 | 68 |
| AOCI, balance at the end of the period                                                                                                                                                       | 30              | 36 | 27 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 9               | 7 | (7) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 1               | 2 | 12 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | (2)             | 0 | 2 |
| OCI                                                                                                                                                                                          | (1)             | 2 | 14 |
| AOCI, balance at the end of the period                                                                                                                                                       | 8               | 9 | 7 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 27              | 20 | (34) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | 1               | 10 | 50 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | (6)             | (3) | 4 |
| OCI                                                                                                                                                                                          | (5)             | 7 | 54 |
| AOCI, balance at the end of the period                                                                                                                                                       | 22              | 27 | 20 |
| Accumulated Net Unrealized Gain (Loss) on Life Policy Reserves, Reinsurance Recoverable And Other                                                                                            |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 29              | (444) | (560) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | (42)            | 473 | 116 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 0               | 0 | 0 |
| OCI                                                                                                                                                                                          | (42)            | 473 | 116 |
| AOCI, balance at the end of the period                                                                                                                                                       | (13)            | 29 | (444) |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 5               | (94) | (118) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | (8)             | 99 | 24 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 0               | 0 | 0 |
| OCI                                                                                                                                                                                          | (8)             | 99 | 24 |
| AOCI, balance at the end of the period                                                                                                                                                       | (3)             | 5 | (94) |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 24              | (350) | (442) |
| OCI before investment gains and losses, net, recognized in net income                                                                                                                        | (34)            | 374 | 92 |
| Investment gains and losses, net, recognized in net income                                                                                                                                   | 0               | 0 | 0 |
| OCI                                                                                                                                                                                          | (34)            | 374 | 92 |
| AOCI, balance at the end of the period                                                                                                                                                       | (10)            | 24 | (350) |
| Accumulated Net Unrealized Gain (Loss) on Life Policy Reserves, Reinsurance Recoverable And Other | Previously Reported                                                                      |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 29              | (444) | (10) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 29 | (444) |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 5               | (94) | (2) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 5 | (94) |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 24              | (350) | (8) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 24 | (350) |
| Accumulated Net Unrealized Gain (Loss) on Life Policy Reserves, Reinsurance Recoverable And Other | Adjustment to purchase price                                                             |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 0               | 0 | (550) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 0 | 0 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 0               | 0 | (116) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 0 | 0 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 0               | 0 | (434) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 0 | 0 |
| Accumulated Other Comprehensive Income (Loss)                                                                                                                                                |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (782)           | 375 | 425 |
| Investments OCI                                                                                                                                                                              | 277             | (1,639) | (234) |
| Pension obligations OCI                                                                                                                                                                      | (6)             | 9 | 68 |
| Life policy reserves, reinsurance recoverable and other OCI                                                                                                                                  | (42)            | 473 | 116 |
| Total OCI                                                                                                                                                                                    | 229             | (1,157) | (50) |
| AOCI, balance at the end of the period                                                                                                                                                       | (553)           | (782) | 375 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (168)           | 78 | 90 |
| Investments OCI                                                                                                                                                                              | 59              | (347) | (50) |
| Pension obligations OCI                                                                                                                                                                      | (1)             | 2 | 14 |
| Life policy reserves, reinsurance recoverable and other OCI                                                                                                                                  | (8)             | 99 | 24 |
| Total OCI                                                                                                                                                                                    | 50              | (246) | (12) |
| AOCI, balance at the end of the period                                                                                                                                                       | (118)           | (168) | 78 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (614)           | 297 | 335 |
| Investments OCI                                                                                                                                                                              | 218             | (1,292) | (184) |
| Pension obligations OCI                                                                                                                                                                      | (5)             | 7 | 54 |
| Life policy reserves, reinsurance recoverable and other OCI                                                                                                                                  | (34)            | 374 | 92 |
| Total OCI                                                                                                                                                                                    | 179             | (911) | (38) |
| AOCI, balance at the end of the period                                                                                                                                                       | (435)           | (614) | 297 |
| Accumulated Other Comprehensive Income (Loss) | Previously Reported                                                                                                                          |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (782)           | 375 | 975 |
| AOCI, balance at the end of the period                                                                                                                                                       |            | (782) | 375 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (168)           | 78 | 206 |
| AOCI, balance at the end of the period                                                                                                                                                       |            | (168) | 78 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (614)           | 297 | 769 |
| AOCI, balance at the end of the period                                                                                                                                                       |            | (614) | 297 |
| Accumulated Other Comprehensive Income (Loss) | Adjustment to purchase price                                                                                                                 |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 0               | 0 | (550) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 0 | 0 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 0               | 0 | (116) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | 0 | 0 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | $ 0             | 0 | (434) |
| AOCI, balance at the end of the period                                                                                                                                                       |            | $ 0 | $ 0 |

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Other Comprehensive Income (Loss), Available-for-sale Securities and Other Assets Adjustment, before Tax
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Other Comprehensive Income (Loss), Deferred Acquisition Costs, Life Policy Reserves and Other Adjustment, before Tax
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Other Comprehensive Income (Loss), Deferred Acquisition Costs, Life Policy Reserves and Other Adjustment, Tax
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| - Definition
Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).
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| - Definition
Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.
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| - Definition
Amount before tax and reclassification adjustments of other comprehensive income (loss).
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Amount after tax, before reclassification adjustments of other comprehensive income (loss).
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| - Definition
Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).
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