Policyholder Obligations - Policyholder Contract Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Account Balance	$ 541.1	$ 608.0
United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Account Balance	448.4	513.8
Fair Value of Collateral Pledged	547.7	661.3
FHLB of Chicago Common Stock Owned at Cost	14.7	17.7
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	448.4	513.8
KMPR - Universal Life-type Policyholder Account Balances
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Account Balance	$ 92.7	$ 94.2

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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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).

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Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense.

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

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