Reserve for Property and Casualty Insurance Claims and Claims Expense - Schedule of Average Annual Percentage Payout of Incurred Claims by Age, Net of Recoverables (Details)	Dec. 31, 2023
Auto insurance – liability coverage
Claims Development [Line Items]
1 year	36.60%
2 years	29.20%
3 years	13.60%
4 years	8.60%
5 years	5.60%
Auto insurance - physical damage coverage
Claims Development [Line Items]
1 year	95.00%
2 years	5.00%
3 years	(0.40%)
4 years	(0.10%)
5 years	0.00%
Homeowners
Claims Development [Line Items]
1 year	70.80%
2 years	22.50%
3 years	2.80%
4 years	0.80%
5 years	0.90%

Short-Duration Insurance Contracts, Historical Claims Duration, Year Four, Net

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Short-Duration Insurance Contracts, Historical Claims Duration, Year Three, Net

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4G
-SubTopic 40
-Topic 944
-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 fourth 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 first 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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