Policyholder Contract Liabilities - Supplemental Financial Information (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 660.9	$ 655.7
Federal Home Loan Bank of Chicago \| United Insurance Company of America
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	563.2	557.4
Fair Value of Collateral Pledged	712.1	629.3
Federal Home Loan Bank of Chicago \| United Insurance Company of America \| FHLB Funding Agreements
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 563.2	$ 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

No definition available.

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- Definition

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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