Short-Duration Insurance Contracts - Average Annual Percentage Payout Of Incurred Claims by Age (Details)	Dec. 31, 2024
Homeowners
2024
Year One	78.20%
Year Two	18.40%
Year Three	2.20%
Year Four	0.60%
Year Five	0.40%
Year Six	0.00%
Year Seven	0.10%
Year Eight	0.00%
Year Nine	0.10%
Year Ten	0.00%
Automobile Liability
2024
Year One	37.20%
Year Two	35.30%
Year Three	14.90%
Year Four	6.80%
Year Five	3.20%
Year Six	1.70%
Year Seven	0.50%
Year Eight	0.20%
Year Nine	0.10%
Year Ten	0.10%
Auto physical damage
2024
Year One	94.80%
Year Two	5.70%
Year Three	(0.50%)
Year Four	0.00%
Year Five	0.00%
Year Six	0.00%
Year Seven	0.00%
Year Eight	0.00%
Year Nine	0.00%
Year Ten	0.00%
Specialty Health
2024
Year One	69.40%
Year Two	28.50%
Year Three	1.10%
Year Four	0.80%
Year Five	0.10%
Year Six	0.10%
Year Seven	0.00%
Year Eight	0.00%
Year Nine	0.00%
Year Ten	0.00%
Group Disability
2024
Year One	30.10%
Year Two	32.70%
Year Three	9.70%
Year Four	3.90%
Year Five	3.20%
Year Six	3.00%
Year Seven	2.90%
Year Eight	2.20%
Year Nine	2.00%
Year Ten	1.70%

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

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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

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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.

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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.

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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 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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