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Losses and LAE - Reserve for Losses and LAE by Segment (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Liability for Claims and Claims Adjustment Expense [Line Items] |  |
Total reserve for losses and LAE | $ 387,650 | $ 354,431
Primary case |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |
Total reserve for losses and LAE | 366,893 | 336,553
Primary IBNR and LAE |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |
Total reserve for losses and LAE | 15,081 | 13,399
Pool and other |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |
Total reserve for losses and LAE | $ 5,676 | $ 4,479

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- Definition The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-11 Reference 2: 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 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 9E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-9E Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (cc) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(13)(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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