Reserves - Schedule of Future Benefit Payments and Expected Gross Premiums (Details) - Long-term care - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Policyholder Account Balance [Line Items]
Expected future benefits payments	$ 829.3	$ 850.0
Expected future gross premiums	$ 69.4	$ 76.2

Amount, before effect of reinsurance, of undiscounted balance for expected future gross premium component of liability for future policy benefit.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 29E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480046/944-40-55-29E

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-6

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- Definition

Amount, before effect of reinsurance, of undiscounted balance for expected future policy benefit and expense component of liability for future policy benefit.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 29F
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480046/944-40-55-29F

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
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