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Reserve for Loss and Loss Expense - Schedule of Exposure to Various Asbestos and Environmental Claims (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Gross | $ 34,649 | $ 26,409 | $ 27,768 | $ 27,773
Net | 27,440 | $ 19,143 | $ 20,329 | $ 21,075
Asbestos |  |  |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Gross | 13,300 |  |  |
Net | 12,000 |  |  |
Landfill sites |  |  |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Gross | 11,200 |  |  |
Net | 7,400 |  |  |
Underground storage tanks |  |  |  |
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Gross | 10,100 |  |  |
Net | $ 8,000 |  |  |

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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 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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