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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Effects of Reinsurance [Line Items] |  |  |  |
Effect in direct loss and loss expense incurred |  |  | $ 187,121 | $ (8,067)
Casualty lines |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Effect in direct loss and loss expense incurred | $ 176,000 | $ (3,500) | $ 211,000 | $ (16,500)

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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/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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