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Loss and Loss Adjustment Expense Reserves - Average Annual Percentage Payout of Incurred Losses and Allocated LAE by Age, Net of Reinsurance (Details) - P&C Insurance and Reinsurance (Ark/WM Outrigger) | Dec. 31, 2025
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Property and Accident & Health |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
1 | 27.40%
2 | 31.90%
3 | 18.40%
4 | 6.40%
5 | 2.90%
6 | 1.90%
7 | 0.40%
8 | 0.90%
9 | 0.20%
10 | 0.10%
Specialty |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
1 | 18.20%
2 | 26.80%
3 | 13.20%
4 | 8.70%
5 | 6.30%
6 | 2.50%
7 | 2.10%
8 | 1.80%
9 | 1.20%
10 | 1.00%
Marine & Energy |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
1 | 12.10%
2 | 27.10%
3 | 17.30%
4 | 12.10%
5 | 6.40%
6 | 6.50%
7 | 0.50%
8 | 0.40%
9 | 0.10%
10 | 0.10%
Casualty-Active |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
1 | 3.80%
2 | 7.50%
3 | 11.40%
4 | 12.90%
5 | 10.00%
6 | 11.20%
7 | 7.20%
8 | 5.10%
9 | 4.20%
10 | 3.40%
Casualty-Runoff |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |
1 | 8.80%
2 | 13.90%
3 | 15.30%
4 | 14.80%
5 | 8.50%
6 | 6.70%
7 | 5.90%
8 | 4.20%
9 | 3.20%
10 | 2.20%

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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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