| **Investments (Analysis Of Cost Or Amortized Cost Gross Unrealized Gains And Losses And Fair Value For Investments) (Details) - USD ($) $ in Millions** | Dec. 31, 2022 | Dec. 31, 2021 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | $ 12,979      | $ 12,230      |
| Fixed maturities, unrealized gains                                                                                                                      | 61            | 808           |
| Fixed maturities, unrealized losses                                                                                                                     | 908           | 16            |
| Fair value of fixed maturities                                                                                                                          | 12,132        | 13,022        |
| Corporate Securities                                                                                                                                    |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 7,412         | 7,043         |
| Fixed maturities, unrealized gains                                                                                                                      | 37            | 467           |
| Fixed maturities, unrealized losses                                                                                                                     | 580           | 13            |
| Fair value of fixed maturities                                                                                                                          | 6,869         | 7,497         |
| States, Municipalities and Political Subdivisions                                                                                                       |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 4,901         | 4,768         |
| Fixed maturities, unrealized gains                                                                                                                      | 24            | 330           |
| Fixed maturities, unrealized losses                                                                                                                     | 303           | 3             |
| Fair value of fixed maturities                                                                                                                          | 4,622         | 5,095         |
| Commercial Mortgage Backed Securities                                                                                                                   |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 250           | 264           |
| Fixed maturities, unrealized gains                                                                                                                      | 0             | 9             |
| Fixed maturities, unrealized losses                                                                                                                     | 16            | 0             |
| Fair value of fixed maturities                                                                                                                          | 234           | 273           |
| United States Government                                                                                                                                |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 196           | 121           |
| Fixed maturities, unrealized gains                                                                                                                      | 0             | 2             |
| Fixed maturities, unrealized losses                                                                                                                     | 5             | 0             |
| Fair value of fixed maturities                                                                                                                          | 191           | 123           |
| Government-Sponsored Enterprises                                                                                                                        |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 186           | 8             |
| Fixed maturities, unrealized gains                                                                                                                      | 0             | 0             |
| Fixed maturities, unrealized losses                                                                                                                     | 3             | 0             |
| Fair value of fixed maturities                                                                                                                          | 183           | 8             |
| Foreign Government                                                                                                                                      |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Total                                                                                                                                                   | 34            | 26            |
| Fixed maturities, unrealized gains                                                                                                                      | 0             | 0             |
| Fixed maturities, unrealized losses                                                                                                                     | 1             | 0             |
| Fair value of fixed maturities                                                                                                                          | 33            | 26            |
| Fixed Maturities                                                                                                                                        |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | 908           | 16            |
| Fixed Maturities | Corporate Securities                                                                                                                 |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | 580           | 13            |
| Fixed Maturities | States, Municipalities and Political Subdivisions                                                                                    |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | 303           | 3             |
| Fixed Maturities | Commercial Mortgage Backed Securities                                                                                                |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | 16            | 0             |
| Fixed Maturities | United States Government                                                                                                             |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | 5             | 0             |
| Fixed Maturities | Government-Sponsored Enterprises                                                                                                     |          |          |
| **Schedule of Available-for-sale Securities**                                                                                                           |          |          |
| Fixed maturities, unrealized losses                                                                                                                     | $ 3           | $ 0           |

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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
+ References
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| - Definition
Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
+ References
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| - Definition
Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
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| - Definition
Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
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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.
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No definition available.
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