| **Income Taxes (Differences Between The 21 Percent Statutory Income Tax Rate And Effective Income Tax Rate) (Details) - USD ($) $ in Millions** | 12 Months Ended |
|-------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Increase (decrease) resulting from:**                                                                                                         |            |   |   |
| Tax at statutory rate:                                                                                                                          | $ (146)         | $ 771 | $ 315 |
| Tax-exempt income from municipal bonds                                                                                                          | (20)            | (20) | (20) |
| Dividend received exclusion                                                                                                                     | (21)            | (20) | (17) |
| Effective Income Tax Rate Reconciliation, Tax Accounting Method Changes, Amount                                                                 | (34)            | 0 | 0 |
| Other                                                                                                                                           | 14              | (7) | 5 |
| Total provision (benefit) for income taxes                                                                                                      | $ (207)         | $ 724 | $ 283 |
| **Tax at statutory rate:**                                                                                                                      |            |   |   |
| Tax at statutory rate (percentage):                                                                                                             | 21.00%          | 21.00% | 21.00% |
| Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent                                                                            | 2.90%           | (0.50%) | (1.30%) |
| Dividend received exclusion (percentage)                                                                                                        | 3.00%           | (0.50%) | (1.10%) |
| Effective Income Tax Rate Reconciliation, Tax Accounting Method Changes, Percent                                                                | 4.90%           | 0.00% | 0.00% |
| Other (percentage)                                                                                                                              | (1.90%)         | (0.30%) | 0.30% |
| Effective tax, percentage                                                                                                                       | 29.90%          | 19.70% | 18.90% |

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).
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