Policyholder Contract Liabilities - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, amount of advances	$ 0.0	$ 81.0	$ 85.0
Policyholder Account Balance, Weighted Average Crediting Rate	5.10%
Policyholder Account Balance, Cash Surrender Value	$ 98.2	100.0
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Net	294.1	311.4
FHLB of Chicago \| United Insurance
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, amount of advances	122.5	334.8
Payments of FHLBank borrowings	$ 166.1	$ 135.7

Amount of cash to be paid to policyholder upon termination and surrender of long-duration contract issued by insurance entity.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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Amount of expected guaranteed benefits in excess of the projected account balances for minimum guaranteed benefit contracts, net of reinsurance recoverables, as of the balance sheet date.

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Weighted-average crediting rate for liability for policyholder account balance, calculated at a point in time.

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Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

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