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LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES - Schedule of Net Prior Year Reserve Development by Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Liability for Claims and Claims Adjustment Expense |  |  |  |
Prior years | $ (817) | $ 5,655 | $ (8,082) | $ 943
Operating Segments |  |  |  |
Liability for Claims and Claims Adjustment Expense |  |  |  |
Prior years |  |  | (6,126) | 5,330
Operating Segments | Open Market |  |  |  |
Liability for Claims and Claims Adjustment Expense |  |  |  |
Prior years | (855) | 5,315 | (4,810) | 3,782
Operating Segments | Innovations |  |  |  |
Liability for Claims and Claims Adjustment Expense |  |  |  |
Prior years | 648 | (94) | (1,316) | 1,548
Corporate |  |  |  |
Liability for Claims and Claims Adjustment Expense |  |  |  |
Prior years | $ (610) | $ 434 | $ (1,956) | $ (4,387)

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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
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