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Reserves For Losses And Loss Expenses (Supplementary Information Regarding Average Historical Claims Duration) (Details) | Dec. 31, 2023
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Insurance | Other liability |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 6.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 13.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 15.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 15.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 12.90%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 10.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 7.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 5.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 4.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 3.30%
Insurance | Workers' compensation |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 24.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 30.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 16.00%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 9.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 5.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 3.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 2.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 1.70%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 1.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 1.00%
Insurance | Professional liability |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 7.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 17.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 17.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 14.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 9.00%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 9.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 5.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 2.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 4.00%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 2.00%
Insurance | Auto |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 34.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 20.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 15.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 11.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 7.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 3.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 1.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 0.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 0.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 0.30%
Insurance | Short-tail lines |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 54.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 33.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 5.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 2.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 1.00%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 0.90%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 0.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 0.30%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 0.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 0.30%
Reinsurance & Monoline Excess | Casualty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 4.70%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 10.00%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 11.70%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 13.90%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 11.70%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 10.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 8.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 5.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 4.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 3.70%
Reinsurance & Monoline Excess | Monoline excess |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 7.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 5.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 3.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 2.70%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 3.40%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 3.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 4.90%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 3.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 3.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 3.50%
Reinsurance & Monoline Excess | Property |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 1 | 28.80%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 2 | 33.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 3 | 17.10%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 4 | 5.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 5 | 3.50%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 6 | 1.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 7 | 1.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 8 | 0.60%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 9 | 0.20%
Average annual percentage payout of incurred claims by age, net of reinsurance, Year 10 | 0.00%

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