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RETROCESSION - Narrative (Details) - Three Reinsurers - Total Loss and Loss Adjustment Expense Recoverability - Reinsurance Concentration Risk - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
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Jun. 30, 2025 | Dec. 31, 2024
Ceded Credit Risk |  |
Concentration risk percentage | 10.00% | 10.00%
Loss and loss adjustment expenses ceded | $ 53.3 | $ 49.5

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