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Third-Party Reinsurance - Remaining Gross and Net Reinsurance Recoverables (Details) - Ark $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items] |
Gross | $ 368.2
Net | 287.5
Ark |
Segment Reporting Information [Line Items] |
Ceded | $ (15.6)
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 | $ 80.7
A+ or better |
Segment Reporting Information [Line Items] |
Gross | 204.0
Net | $ 204.0
A+ or better | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |
Segment Reporting Information [Line Items] |
% of Total | 71.00%
A+ or better | Ceded Credit Risk, Secured |
Segment Reporting Information [Line Items] |
Collateral | $ 0.0
A- to A |
Segment Reporting Information [Line Items] |
Gross | 76.2
Net | $ 76.2
A- to A | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |
Segment Reporting Information [Line Items] |
% of Total | 26.50%
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] |
Gross | 88.0
Net | $ 7.3
B++ or lower and not rated | Reinsurance Recoverable Including Reinsurance Premium Paid | Reinsurer Concentration Risk |
Segment Reporting Information [Line Items] |
% of Total | 2.50%
B++ or lower and not rated | Ceded Credit Risk, Secured |
Segment Reporting Information [Line Items] |
Collateral | $ 80.7

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