| **Undiscounted and Discounted Future Benefit Payments and Gross Premiums (Details) - Life Policy Reserves - USD ($) $ in Millions** | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 |
|-------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|
| Term Life Insurance                                                                                                                 |          |          |          |          |
| **Liability for Future Policy Benefit, Activity**                                                                                   |          |          |          |          |
| Undiscounted expected future benefit payments                                                                                       | $ 4,791       | $ 4,655       |          |          |
| Undiscounted expected future gross premiums                                                                                         | 4,374         | 4,436         |          |          |
| Liability for Future Policy Benefit, Expected Future Policy Benefit, before Reinsurance, after Discount Rate Change                 | 2,751         | 2,584         | $ 2,993       | $ 3,222       |
| Discounted expected future gross premiums                                                                                           | 2,652         | 2,582         |          |          |
| Whole Life Insurance                                                                                                                |          |          |          |          |
| **Liability for Future Policy Benefit, Activity**                                                                                   |          |          |          |          |
| Undiscounted expected future benefit payments                                                                                       | 1,648         | 1,562         |          |          |
| Undiscounted expected future gross premiums                                                                                         | 659           | 606           |          |          |
| Liability for Future Policy Benefit, Expected Future Policy Benefit, before Reinsurance, after Discount Rate Change                 | 657           | 614           | $ 826         | $ 843         |
| Discounted expected future gross premiums                                                                                           | $ 409         | $ 368         |          |          |

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Amount, before effect of reinsurance, of discounted balance for expected future gross premium component of liability for future policy benefit.
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Amount, before effect of reinsurance, of undiscounted balance for expected future gross premium component of liability for future policy benefit.
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Amount, before effect of reinsurance and after current period update of cash flow assumption and discount rate change, of expected future policy benefit and expense component of liability for future policy benefit.
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Amount, before effect of reinsurance, of undiscounted balance for expected future policy benefit and expense component of liability for future policy benefit.
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