Fair Value Measurements - Balance Sheet Grouping (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Carrying Value
Loans to Policyholders	$ 281.8	$ 283.4
Short-Term Investments	418.5	278.4
418500000	418.5	278.4
Mortgage Loans	98.5	91.1
Long-term Debt	1,388.6	1,386.9
Policyholder Obligations	656.3	701.3
Loans to Policyholders	281.8
Fair Value
Short-term Investments	418.5	278.4
Long-term Debt	1,158.0	1,195.1
Company-Owned Life Insurance	506.9	586.5
Equity Securities at Modified Cost	33.1	38.4
Equity Securities, FV-NI	33.1	38.4
Fair Value Measured at Net Asset Value Per Share
Fair Value
Equity Securities, FV-NI	5.3	8.3
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	103.3	96.3
Federal Home Loan Bank of Chicago
Fair Value
Policyholder Obligations	557.4	601.0
Loans to Policyholders
Fair Value
Loans	281.8	283.4
Mortgage Loans
Fair Value
Loans	98.5	91.1
United Insurance Company of America \| FHLB Funding Agreements \| Federal Home Loan Bank of Chicago
Carrying Value
Policyholder Obligations	$ 557.4	$ 601.0

Fair Value, Alternative Investments, Entities That Calculate Net Asset Value, Unfunded Commitments

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Loans, Gross, Insurance Policy, Including Disposal Group And Discontinued Operations

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Other Short-term Investments, Fair Value Disclosure

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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.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

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