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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit Reserves (Historical Claims Duration) (Details) | Dec. 31, 2022
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Medical Professional Liability | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 3.60%
Year 2 | 17.00%
Year 3 | 23.00%
Year 4 | 18.00%
Year 5 | 11.90%
Year 6 | 8.20%
Year 7 | 4.70%
Year 8 | 2.30%
Year 9 | 1.00%
Year 10 | 0.90%
Other Professional Liability and Management Liability | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 6.60%
Year 2 | 21.00%
Year 3 | 20.70%
Year 4 | 16.20%
Year 5 | 10.30%
Year 6 | 6.00%
Year 7 | 4.30%
Year 8 | 4.80%
Year 9 | 1.40%
Year 10 | 0.50%
Surety | Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 19.00%
Year 2 | 40.50%
Year 3 | 20.20%
Year 4 | 3.60%
Year 5 | 2.10%
Year 6 | 4.80%
Year 7 | (1.70%)
Year 8 | 0.40%
Year 9 | (0.60%)
Year 10 | 0.00%
Commercial Auto | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 26.10%
Year 2 | 22.00%
Year 3 | 17.60%
Year 4 | 13.90%
Year 5 | 10.40%
Year 6 | 4.80%
Year 7 | 1.70%
Year 8 | 0.50%
Year 9 | 0.00%
Year 10 | 0.00%
General Liability | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 3.90%
Year 2 | 13.70%
Year 3 | 17.10%
Year 4 | 18.80%
Year 5 | 14.30%
Year 6 | 9.40%
Year 7 | 5.70%
Year 8 | 4.60%
Year 9 | 2.10%
Year 10 | 0.60%
Workers' Compensation | Commercial |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 15.30%
Year 2 | 22.30%
Year 3 | 13.70%
Year 4 | 9.40%
Year 5 | 6.10%
Year 6 | 2.30%
Year 7 | 1.10%
Year 8 | 1.40%
Year 9 | 1.00%
Year 10 | 1.10%
Excluding Hardy | International |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 18.30%
Year 2 | 22.50%
Year 3 | 10.40%
Year 4 | 7.10%
Year 5 | 6.00%
Year 6 | 6.20%
Year 7 | 6.70%
Year 8 | 2.90%
Year 9 | 2.50%
Year 10 | 1.30%
Hardy | International |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Year 1 | 19.70%
Year 2 | 34.00%
Year 3 | 13.40%
Year 4 | 7.00%
Year 5 | 4.40%
Year 6 | 3.90%
Year 7 | 0.60%
Year 8 | 2.10%
Year 9 | 1.00%
Year 10 | 0.70%

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4G -URI https://asc.fasb.org/extlink&oid=116884468&loc=SL65671329-158438 + Details
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