Policyholder Obligations - Policyholder Contract Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 618.3	$ 655.7
United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	521.3	557.4
Fair Value of Collateral Pledged	666.1	629.3
FHLB of Chicago Common Stock Owned at Cost	16.4	16.6
Universal Life-type Policyholder Account Balances
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	97.0	98.3
Funding Agreements \| United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 521.3	$ 557.4

Carrying value as of the balance sheet date of the sum of the obligations to contract holders to provide to them an agreed upon rate of return pursuant to the terms of the underlying contract. These contracts represent lending by the contract holders to the entity in return for a guaranteed (primarily fixed) interest rate until maturity, unless called earlier if the contracts provide that option to the contract holders (usually institutions). There is little or no insurance risk for the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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+ References

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 325
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477974/942-325-45-1

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Fair value of the securities pledged as collateral against securities loaned.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-12

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