Debt - Collateralized Investment Borrowings (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total	$ 778.7	$ 909.0
Federal Home Loan Bank of Chicago \| United Insurance Company of America
Debt Instrument [Line Items]
Due in One Year or Less	107.8
Due after One Year to Two Years	27.1
Due after Two Years	2.7
Total	$ 137.6
Due in One Year or Less \| Federal Home Loan Bank of Chicago \| United Insurance Company of America
Debt Instrument [Line Items]
Weighted-average Interest Rate	2.68%
Due after One Year to Two Years \| Federal Home Loan Bank of Chicago \| United Insurance Company of America
Debt Instrument [Line Items]
Weighted-average Interest Rate	2.73%
Due after Two Years \| Federal Home Loan Bank of Chicago \| United Insurance Company of America
Debt Instrument [Line Items]
Weighted-average Interest Rate	2.34%

Long-term Debt, Maturities, Repayments of Principal after Year Two

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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