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v3.25.2

Transactions With Related Parties (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Mar. 31, 2025 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Net premiums written | $ 4,348 | $ 3,781 | $ 8,863 | $ 7,866 |  |  |  |
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses | 9,044 | $ 7,473 | 9,044 | 7,473 | $ 8,969 | $ 8,260 | $ 7,509 | $ 7,064
Reinsurance balances payable | 2,841 |  | 2,841 |  |  | 2,137 |  |
Other assets | 6,684 |  | 6,684 |  |  | 6,231 |  |
Other liabilities | 3,225 |  | 3,225 |  |  | 3,039 |  |
Operating affiliates | Premia |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Funds held asset | 127 |  | 127 |  |  | 137 |  |
Operating affiliates | Somers |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Net premiums written |  |  | 419 | $ 428 |  |  |  |
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses | 1,800 |  | 1,800 |  |  | 1,600 |  |
Reinsurance balances payable | 602 |  | 602 |  |  | $ 489 |  |
Equity Method Investee | Greysbridge Holdings Ltd |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Other assets | 290 |  | 290 |  |  |  |  |
Other liabilities | $ 290 |  | $ 290 |  |  |  |  |

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