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Reserve for Loss and Loss Expense - Schedule of Roll Forward of Gross and Net Asbestos and Environmental Incurred Losses and Loss Expenses and Related Reserves (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Gross |  |  |
Reserve for loss and loss expense at beginning of year, gross | $ 26,409 | $ 27,768 | $ 27,773
Incurred loss and loss expense, gross | 33,053 | 1,064 | 704
Less: loss and loss expense paid, Gross | (24,813) | (2,423) | (709)
Reserve for loss and loss expense at the end of year, gross | 34,649 | 26,409 | 27,768
Net |  |  |
Reserve for loss and loss expense at beginning of year, net | 19,143 | 20,329 | 21,075
Incurred loss and loss expense, Net | 19,754 | 748 | (205)
Less: loss and loss expense paid, Net | (11,457) | (1,934) | (541)
Reserve for loss and loss expense at the end of year, net | 27,440 | 19,143 | 20,329
Asbestos |  |  |
Gross |  |  |
Reserve for loss and loss expense at beginning of year, gross | 4,856 | 5,891 | 6,115
Incurred loss and loss expense, gross | 32,721 | 603 | 8
Less: loss and loss expense paid, Gross | (24,261) | (1,638) | (232)
Reserve for loss and loss expense at the end of year, gross | 13,316 | 4,856 | 5,891
Net |  |  |
Reserve for loss and loss expense at beginning of year, net | 3,537 | 4,660 | 4,884
Incurred loss and loss expense, Net | 19,634 | 515 | 8
Less: loss and loss expense paid, Net | (11,202) | (1,638) | (232)
Reserve for loss and loss expense at the end of year, net | 11,969 | 3,537 | 4,660
Environmental |  |  |
Gross |  |  |
Reserve for loss and loss expense at beginning of year, gross | 21,553 | 21,877 | 21,658
Incurred loss and loss expense, gross | 332 | 461 | 696
Less: loss and loss expense paid, Gross | (552) | (785) | (477)
Reserve for loss and loss expense at the end of year, gross | 21,333 | 21,553 | 21,877
Net |  |  |
Reserve for loss and loss expense at beginning of year, net | 15,606 | 15,669 | 16,191
Incurred loss and loss expense, Net | 120 | 233 | (213)
Less: loss and loss expense paid, Net | (255) | (296) | (309)
Reserve for loss and loss expense at the end of year, net | $ 15,471 | $ 15,606 | $ 15,669

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- Definition Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, before estimated recoveries from reinsurers. + References Reference 1: 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 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
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- Definition Amount, before effects of reinsurance, of expense for claims incurred and costs incurred in the claim settlement process attributable to asbestos and environmental claims. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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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- Definition Amount of cash outflow to settle insured claims and pay costs incurred in the claims settlement process attributable to asbestos and environmental claims. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 17 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-17 + Details
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- Definition Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, net of estimated reinsurance recoveries. + References Reference 1: 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 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
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