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v3.25.4

Allowance for Expected Credit Losses - Ceded credit risk (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Concentration Risk [Line Items] |  |  |  |
Reinsurance recoverable for paid and unpaid claims and claims adjustments |  | $ 9,526 | $ 8,260 | $ 7,064
Reinsurance recoverable | Reinsurer concentration risk | AM Best "A-" Or Better Rating |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk percentage |  | 62.10% | 63.80% |
Reinsurance recoverable | Reinsurer concentration risk | No AM Best rating | All Other Carriers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk percentage | [1] | 37.90% | 36.20% |
Reinsurance recoverable | Reinsurer concentration risk | No AM Best rating | Reinsurance trusts or letters of credit |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk percentage |  | 96.00% | 96.00% |
Shareholders' equity | Reinsurer concentration risk | Largest balance due from any one carrier |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk percentage |  | 8.10% | 7.80% |
[1] | At December 31, 2025 and 2024 period, over 96% of such amounts were collateralized through reinsurance trusts, funds withheld arrangements, letters of credit or other.

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