|**Life Policy and Investment Contract Reserves (Tables)**              | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                
|---------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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|**Liability for Future Policy Benefit, before Reinsurance [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                               
|Reserve For Losses Loss Adjustment Expenses Table                      | This table summarizes our life policy and investment contract reserves:(Dollars in millions)September 30,2022December 31,2021Life policy reserves:Ordinary/traditional life$1,432$1,376Other5252Subtotal1,4841,428Investment contract reserves:Deferred annuities753762Universal life677679Structured settlements131136Other89Subtotal1,5691,586Total life policy and investment contract reserves$3,053$3,014
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|(Dollars in millions)                                                  |                                                                                                                                                                                                                                                                                                                                                                                                               
|Life policy reserves:                                                  |                                                                                                                                                                                                                                                                                                                                                                                                               
|Ordinary/traditional life                                              |                                                                                                                                                                                                                                                                                                                                                                                                               
|Other                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                               
|Subtotal                                                               |                                                                                                                                                                                                                                                                                                                                                                                                               
|Investment contract reserves:                                          |                                                                                                                                                                                                                                                                                                                                                                                                               
|Deferred annuities                                                     |                                                                                                                                                                                                                                                                                                                                                                                                               
|Universal life                                                         |                                                                                                                                                                                                                                                                                                                                                                                                               
|Structured settlements                                                 |                                                                                                                                                                                                                                                                                                                                                                                                               
|Other                                                                  |                                                                                                                                                                                                                                                                                                                                                                                                               
|Subtotal                                                               |                                                                                                                                                                                                                                                                                                                                                                                                               
|Total life policy and investment contract reserves                     |                                                                                                                                                                                                                                                                                                                                                                                                               
|                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                               

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