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v3.25.4

Third-Party Reinsurance - Remaining Gross and Net Reinsurance Recoverables (Details) - Ark Insurance Holdings Limited/Outrigger - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024
Segment Reporting Information [Line Items] |  |
Gross | $ 625.9 |
Collateral | 836.1 | $ 589.0
Net | $ 563.6 |
Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |  |
Segment Reporting Information [Line Items] |  |
% of Total | 100.00% |
Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 62.3 |
A+ or better |  |
Segment Reporting Information [Line Items] |  |
Gross | 404.0 |
Net | $ 404.0 |
A+ or better | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |  |
Segment Reporting Information [Line Items] |  |
% of Total | 71.70% |
A+ or better | Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 0.0 |
A- to A |  |
Segment Reporting Information [Line Items] |  |
Gross | 147.7 |
Net | $ 147.7 |
A- to A | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |  |
Segment Reporting Information [Line Items] |  |
% of Total | 26.20% |
A- to A | Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 0.0 |
B++ or lower and not rated |  |
Segment Reporting Information [Line Items] |  |
Gross | 74.2 |
Net | 11.9 |
B++ or lower and not rated | Ark |  |
Segment Reporting Information [Line Items] |  |
Gross | (34.7) |
Collateral | $ (34.7) |
B++ or lower and not rated | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |  |
Segment Reporting Information [Line Items] |  |
% of Total | 2.10% |
B++ or lower and not rated | Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 62.3 |

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