| **Deferred Policy Acquisition Costs (Deferred Policy Acquisition Costs And Asset Reconciliation Including The Amortized Deferred Policy Acquisition Costs) (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended                                                                            |
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| **Deferred Costs [Roll Forward]**                                                                                                                                                                                     |                                                                                       |   |   |
| Deferred policy acquisition costs asset at January 1                                                                                                                                                                  | $ 565us-gaap_DeferredPolicyAcquisitionCosts                                                | $ 470us-gaap_DeferredPolicyAcquisitionCosts | $ 477us-gaap_DeferredPolicyAcquisitionCosts |
| Capitalized deferred policy acquisition costs                                                                                                                                                                         | 827us-gaap_DeferredPolicyAcquisitionCostsAdditions                                         | 802us-gaap_DeferredPolicyAcquisitionCostsAdditions | 734us-gaap_DeferredPolicyAcquisitionCostsAdditions |
| Amortized deferred policy acquisition costs                                                                                                                                                                           | (807)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses      | (758)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses | (706)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses |
| Amortized shadow deferred policy acquisition costs                                                                                                                                                                    | (7)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseUnrealizedInvestmentGainsLosses | 51us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseUnrealizedInvestmentGainsLosses | (35)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseUnrealizedInvestmentGainsLosses |
| Deferred policy acquisition costs asset at December 31                                                                                                                                                                | $ 578us-gaap_DeferredPolicyAcquisitionCosts                                                | $ 565us-gaap_DeferredPolicyAcquisitionCosts | $ 470us-gaap_DeferredPolicyAcquisitionCosts |

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| - Definition
Amount of amortization of deferred policy acquisition costs due to realized investment gains or losses.
+ References
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| - Definition
Amount of increase (decrease) in deferred policy acquisition cost (DAC) due to unrealized investment gain (loss).
+ References
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| - Definition
Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.
+ References
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| - Definition
Total amount of policy acquisition costs capitalized during the income statement period.
+ References
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