| **Reinsurance (Narrative) (Details) - USD ($) $ in Millions** | Mar. 31, 2024 | Dec. 31, 2023 |
|---------------------------------------------------------------|---------------|---------------|
| Consolidated Property and Casualty Insurance                  |          |          |
| **Reinsurance for Insurance Companies, by Product Segment**   |          |          |
| Premium Receivable, Allowance for Credit Loss                 | $ 16          | $ 16          |

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| - References
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| - Definition
The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.
+ References
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