Loss And Loss Adjustment Expense Reserves - Average Annual Percentage Payout of Incurred Claims by Age (Details)	Dec. 31, 2024
Property insurance product line, automobile
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Short-duration insurance contracts, historical claims duration, year one	57.80%
Short-duration insurance contracts, historical claims duration, year two	19.60%
Short-duration insurance contracts, historical claims duration, year three	9.70%
Short-duration insurance contracts, historical claims duration, year four	6.00%
Short-duration insurance contracts, historical claims duration, year five	3.10%
Short-duration insurance contracts, historical claims duration, year six	1.50%
Short-duration insurance contracts, historical claims duration, year seven	0.70%
Short-duration insurance contracts, historical claims duration, year eight	0.30%
Short-duration insurance contracts, historical claims duration, year nine	0.10%
Short-duration insurance contracts, historical claims duration, year ten	0.00%
Property insurance product line, homeowners'
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Short-duration insurance contracts, historical claims duration, year one	66.30%
Short-duration insurance contracts, historical claims duration, year two	23.00%
Short-duration insurance contracts, historical claims duration, year three	4.30%
Short-duration insurance contracts, historical claims duration, year four	2.40%
Short-duration insurance contracts, historical claims duration, year five	1.50%
Short-duration insurance contracts, historical claims duration, year six	0.90%
Short-duration insurance contracts, historical claims duration, year seven	0.30%
Short-duration insurance contracts, historical claims duration, year eight	0.30%
Short-duration insurance contracts, historical claims duration, year nine	0.10%
Short-duration insurance contracts, historical claims duration, year ten	0.00%
Property insurance product line, commercial property
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Short-duration insurance contracts, historical claims duration, year one	31.30%
Short-duration insurance contracts, historical claims duration, year two	17.50%
Short-duration insurance contracts, historical claims duration, year three	10.90%
Short-duration insurance contracts, historical claims duration, year four	10.90%
Short-duration insurance contracts, historical claims duration, year five	5.80%
Short-duration insurance contracts, historical claims duration, year six	8.00%
Short-duration insurance contracts, historical claims duration, year seven	6.60%
Short-duration insurance contracts, historical claims duration, year eight	2.00%
Short-duration insurance contracts, historical claims duration, year nine	2.00%
Short-duration insurance contracts, historical claims duration, year ten	0.20%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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

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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.

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Percentage of average annual payout, after reinsurance, in the fourth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

+ References

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Percentage of average annual payout, after reinsurance, in the ninth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

+ References

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Percentage of average annual payout, after reinsurance, in the first year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

+ References

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Percentage of average annual payout, after reinsurance, in the seventh year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

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Percentage of average annual payout, after reinsurance, in the sixth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

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Percentage of average annual payout, after reinsurance, in the tenth year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

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Percentage of average annual payout, after reinsurance, in the third year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

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Percentage of average annual payout, after reinsurance, in the second year after a claim is incurred, beginning with the earliest accident year disclosed for short-duration insurance contracts.

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