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v3.24.3

Third-Party Reinsurance - Remaining Gross and Net Reinsurance Recoverables (Details) - P&C Insurance and Reinsurance (Ark/WM Outrigger) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Segment Reporting Information [Line Items] |  |
Reinsurance recoverables | $ 535.1 |
Collateral | 748.0 | $ 442.0
Net | 454.0 |
Reinsurance recoverables on unpaid losses | 507.2 | 340.8
Ark |  |
Segment Reporting Information [Line Items] |  |
Reinsurance recoverables on unpaid losses | $ (28.0) | $ (15.6)
Reinsurer Concentration Risk | Reinsurance Recoverable Including Reinsurance Premium Paid |  |
Segment Reporting Information [Line Items] |  |
% of Total | 100.00% |
Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 81.1 |
A+ or better |  |
Segment Reporting Information [Line Items] |  |
Reinsurance recoverables | 358.1 |
Net | $ 358.1 |
A+ or better | Reinsurer Concentration Risk | Reinsurance Recoverable Including Reinsurance Premium Paid |  |
Segment Reporting Information [Line Items] |  |
% of Total | 78.90% |
A+ or better | Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 0.0 |
A- to A |  |
Segment Reporting Information [Line Items] |  |
Reinsurance recoverables | 84.2 |
Net | $ 84.2 |
A- to A | Reinsurer Concentration Risk | Reinsurance Recoverable Including Reinsurance Premium Paid |  |
Segment Reporting Information [Line Items] |  |
% of Total | 18.50% |
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] |  |
Reinsurance recoverables | 92.8 |
Net | $ 11.7 |
B++ or lower and not rated | Reinsurer Concentration Risk | Reinsurance Recoverable Including Reinsurance Premium Paid |  |
Segment Reporting Information [Line Items] |  |
% of Total | 2.60% |
B++ or lower and not rated | Ceded Credit Risk, Secured |  |
Segment Reporting Information [Line Items] |  |
Collateral | $ 81.1 |

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