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Claim and Claim Adjustment Expense Reserves (Historical Claims Duration) (Details) | Dec. 31, 2024
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Medical Professional Liability | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 3.60%
Year 2 | 16.30%
Year 3 | 21.80%
Year 4 | 16.60%
Year 5 | 12.70%
Year 6 | 8.90%
Year 7 | 5.70%
Year 8 | 3.20%
Year 9 | 1.10%
Year 10 | 1.60%
Other Professional Liability and Management Liability | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 6.50%
Year 2 | 19.60%
Year 3 | 19.20%
Year 4 | 14.70%
Year 5 | 10.50%
Year 6 | 6.90%
Year 7 | 5.60%
Year 8 | 6.10%
Year 9 | 2.50%
Year 10 | 0.60%
Surety | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 17.30%
Year 2 | 41.00%
Year 3 | 16.40%
Year 4 | 8.10%
Year 5 | 3.90%
Year 6 | 6.20%
Year 7 | (2.30%)
Year 8 | (0.30%)
Year 9 | 1.10%
Year 10 | 0.00%
Commercial Auto | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 23.70%
Year 2 | 22.30%
Year 3 | 18.40%
Year 4 | 14.60%
Year 5 | 10.50%
Year 6 | 5.10%
Year 7 | 2.40%
Year 8 | 0.90%
Year 9 | 0.50%
Year 10 | 1.10%
General Liability | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 3.40%
Year 2 | 12.50%
Year 3 | 15.70%
Year 4 | 16.80%
Year 5 | 13.80%
Year 6 | 9.20%
Year 7 | 7.10%
Year 8 | 5.70%
Year 9 | 3.20%
Year 10 | 1.20%
Workers' Compensation | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 16.80%
Year 2 | 23.40%
Year 3 | 14.20%
Year 4 | 8.80%
Year 5 | 5.90%
Year 6 | 3.80%
Year 7 | 2.30%
Year 8 | 1.20%
Year 9 | 1.00%
Year 10 | 0.60%
Excluding Hardy | International |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 16.20%
Year 2 | 21.00%
Year 3 | 9.60%
Year 4 | 6.50%
Year 5 | 6.10%
Year 6 | 6.50%
Year 7 | 7.50%
Year 8 | 2.70%
Year 9 | 3.90%
Year 10 | 2.30%
Hardy | International |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 15.40%
Year 2 | 28.90%
Year 3 | 15.30%
Year 4 | 8.60%
Year 5 | 5.20%
Year 6 | 6.20%
Year 7 | 1.80%
Year 8 | 3.30%
Year 9 | (0.30%)
Year 10 | (5.10%)

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- Definition Percentage of average annual payout, after reinsurance, in the eighth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 9F -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-9F Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 4G -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-4G + Details
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