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v3.25.4

Liabilities for Outstanding Claims, Losses and Loss Adjustment Expenses (Computation of Historical Claims on Paid and Incurred Claims Data, Net of Reinsurance) (Details) | Dec. 31, 2025
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Core - Commercial Multiple Peril Line [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 33.40%
2 | 24.30%
3 | 9.90%
4 | 8.30%
5 | 7.80%
6 | 5.10%
7 | 4.40%
8 | 1.60%
Core - Workers' Compensation Line [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 22.10%
2 | 29.00%
3 | 15.20%
4 | 8.60%
5 | 4.80%
6 | 3.00%
7 | 2.80%
8 | 1.40%
9 | 1.10%
10 | 0.00%
Core - Commercial Automobile Line [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 12.80%
2 | 18.20%
3 | 19.70%
4 | 19.60%
5 | 12.80%
6 | 7.30%
7 | 2.50%
Core - General Liability And Umbrella - Occurrence [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 3.10%
2 | 9.20%
3 | 13.10%
4 | 16.30%
5 | 14.10%
6 | 9.30%
7 | 8.00%
8 | 9.40%
9 | 3.90%
10 | 3.70%
Specialty Property And Casualty [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 27.50%
2 | 21.40%
3 | 10.10%
4 | 11.30%
5 | 9.30%
6 | 5.80%
7 | 2.60%
8 | 1.70%
Specialty - General Liability - Claims Made [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 13.00%
2 | 25.90%
3 | 19.40%
4 | 12.60%
5 | 9.80%
6 | 4.50%
7 | 3.60%
Personal Automobile Lines [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 27.00%
2 | 29.50%
3 | 19.70%
4 | 12.30%
5 | 6.90%
Homeowners [Member] |
Shortduration Insurance Contracts Historical Claims Duration [Line Items] |
1 | 63.80%
2 | 27.80%
3 | 3.70%
4 | 1.70%

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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://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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- Definition Percentage of average annual payout, after reinsurance, in the fifth 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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