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RETROCESSION - Narrative (Details) - Total Loss and Loss Adjustment Expense Recoverability - Reinsurance Concentration Risk - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
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Sep. 30, 2025 | Dec. 31, 2024
Four Reinsurers |  |
Ceded Credit Risk |  |
Loss and loss adjustment expenses ceded | $ 62.1 |
Three Reinsurers |  |
Ceded Credit Risk |  |
Loss and loss adjustment expenses ceded |  | $ 49.5

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- Definition Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 21 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-21 + Details
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