Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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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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Debt Summary of Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2020	Aug. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 1,243.2		$ 832.8
Federal Home Loan Bank Advances (FHLB)
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 155.0		155.0
Stated interest rate (in hundredths)	1.91%
Senior Notes \| 5.75% Senior Notes due 2023
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 240.6		420.9
Stated interest rate (in hundredths)	5.75%
Debt instrument, face amount	$ 242.3
Senior Notes \| 5.25% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 638.8		0.0
Stated interest rate (in hundredths)	5.25%	5.25%
Debt instrument, face amount	$ 650.0	$ 650.0
Convertible Junior Subordinated Debentures, at 9% per annum, Due 2063
Debt Instrument [Line Items]
Long-term debt, carrying value	$ 208.8		$ 256.9
Stated interest rate (in hundredths)	9.00%