| **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)           | $ (18) | $ 83 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| Income taxes on above of other comprehensive (loss) income                                                                                                                                   | (218)           | 130 | 202 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 1,744           |   |   |
| Other comprehensive (loss) income before tax                                                                                                                                                 | (618)           | 370 | 577 |
| AOCI, balance at the end of the period                                                                                                                                                       | 1,344           | 1,744 |   |
| Accumulated Net Unrealized Investment Gain (Loss)                                                                                                                                            |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 2,719           | 2,335 | 1,875 |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (556)           | 514 | 537 |
| Realized gains (losses) recognized in net income                                                                                                                                             | (69)            | (130) | (77) |
| OCI, portion attributable to Parent                                                                                                                                                          | (625)           | 384 | 460 |
| AOCI, balance at the end of the period                                                                                                                                                       | 2,094           | 2,719 | 2,335 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 942             | 808 | 647 |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (196)           | 181 | 188 |
| Realized gains (losses) recognized in net income                                                                                                                                             | (24)            | (47) | (27) |
| Income taxes on above of other comprehensive (loss) income                                                                                                                                   | (220)           | 134 | 161 |
| AOCI, balance at the end of the period                                                                                                                                                       | 722             | 942 | 808 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 1,777           | 1,527 | 1,228 |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (360)           | 333 | 349 |
| Realized gains (losses) recognized in net income                                                                                                                                             | (45)            | (83) | (50) |
| Other comprehensive (loss) income before tax                                                                                                                                                 | (405)           | 250 | 299 |
| AOCI, balance at the end of the period                                                                                                                                                       | 1,372           | 1,777 | 1,527 |
| Accumulated Defined Benefit Plans Adjustment                                                                                                                                                 |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (36)            | (18) | (101) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (12)            | (21) | 83 |
| Realized gains (losses) recognized in net income                                                                                                                                             | 6               | 3 | 0 |
| OCI, portion attributable to Parent                                                                                                                                                          | (6)             | (18) | 83 |
| AOCI, balance at the end of the period                                                                                                                                                       | (42)            | (36) | (18) |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (12)            | (6) | (35) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (5)             | (7) | 29 |
| Realized gains (losses) recognized in net income                                                                                                                                             | 3               | 1 | 0 |
| Income taxes on above of other comprehensive (loss) income                                                                                                                                   | (2)             | (6) | 29 |
| AOCI, balance at the end of the period                                                                                                                                                       | (14)            | (12) | (6) |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (24)            | (12) | (66) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | (7)             | (14) | 54 |
| Realized gains (losses) recognized in net income                                                                                                                                             | 3               | 2 | 0 |
| Other comprehensive (loss) income before tax                                                                                                                                                 | (4)             | (12) | 54 |
| AOCI, balance at the end of the period                                                                                                                                                       | (28)            | (24) | (12) |
| Accumulated Net Unrealized Gain (Loss) on Deferred Costs, Reserves And Other                                                                                                                 |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (12)            | (16) | (50) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | 14              | 7 | 40 |
| Realized gains (losses) recognized in net income                                                                                                                                             | (1)             | (3) | (6) |
| OCI, portion attributable to Parent                                                                                                                                                          | 13              | 4 | 34 |
| AOCI, balance at the end of the period                                                                                                                                                       | 1               | (12) | (16) |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (3)             | (5) | (17) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | 5               | 3 | 14 |
| Realized gains (losses) recognized in net income                                                                                                                                             | (1)             | (1) | (2) |
| Income taxes on above of other comprehensive (loss) income                                                                                                                                   | 4               | 2 | 12 |
| AOCI, balance at the end of the period                                                                                                                                                       | 1               | (3) | (5) |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | (9)             | (11) | (33) |
| OCI before realized gains (losses) recognized in net income                                                                                                                                  | 9               | 4 | 26 |
| Realized gains (losses) recognized in net income                                                                                                                                             | 0               | (2) | (4) |
| Other comprehensive (loss) income before tax                                                                                                                                                 | 9               | 2 | 22 |
| AOCI, balance at the end of the period                                                                                                                                                       | 0               | (9) | (11) |
| Accumulated Other Comprehensive Income (Loss)                                                                                                                                                |            |   |   |
| **Accumulated Other Comprehensive Income, Before Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 2,671           | 2,301 | 1,724 |
| Investments OCI                                                                                                                                                                              | (625)           | 384 | 460 |
| Pension obligations OCI                                                                                                                                                                      | (6)             | (18) | 83 |
| Life deferred acquisition costs, life policy reserves and other OCI                                                                                                                          | 13              | 4 | 34 |
| Total OCI                                                                                                                                                                                    | (618)           | 370 | 577 |
| AOCI, balance at the end of the period                                                                                                                                                       | 2,053           | 2,671 | 2,301 |
| **Accumulated Other Comprehensive Income, Income Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 927             | 797 | 595 |
| Investments OCI                                                                                                                                                                              | (220)           | 134 | 161 |
| Pension obligations OCI                                                                                                                                                                      | (2)             | (6) | 29 |
| Life deferred acquisition costs, life policy reserves and other OCI                                                                                                                          | 4               | 2 | 12 |
| Total OCI                                                                                                                                                                                    | (218)           | 130 | 202 |
| AOCI, balance at the end of the period                                                                                                                                                       | 709             | 927 | 797 |
| **Accumulated Other Comprehensive Income, Net of Tax**                                                                                                                                       |            |   |   |
| AOCI, balance at the beginning of the period                                                                                                                                                 | 1,744           | 1,504 | 1,129 |
| Investments OCI                                                                                                                                                                              | (405)           | 250 | 299 |
| Pension obligations OCI                                                                                                                                                                      | (4)             | (12) | 54 |
| Life deferred acquisition costs, life policy reserves and other OCI                                                                                                                          | 9               | 2 | 22 |
| Total OCI                                                                                                                                                                                    | (400)           | 240 | 375 |
| AOCI, balance at the end of the period                                                                                                                                                       | $ 1,344         | $ 1,744 | $ 1,504 |

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Amount before tax of increase (decrease) in accumulated in equity from transactions and other events and circumstances from non-owner sources. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).
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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.
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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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Amount before tax of other comprehensive income (loss) attributable to parent entity.
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Amount after tax of other comprehensive income (loss) attributable to parent entity.
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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.
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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.
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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.
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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.
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Amount before tax of reclassification adjustments of other comprehensive income (loss).
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Amount after tax of reclassification adjustments of other comprehensive income (loss).
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