Debt - Carrying Amounts of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 356.9
Unamortized discount and issuance costs	(2.9)	$ (20.0)
Total debt	354.0	358.7
Less: Current maturities	(16.3)	(2.7)
Total long-term debt	337.7	356.0
Notes (primarily with related parties) \| Subordinated Notes Due 2026
Debt Instrument [Line Items]
Long-term debt	0.0	110.0
Senior Revolver \| Line of Credit
Debt Instrument [Line Items]
Long-term debt	40.0	0.0
Senior Term Loan \| Line of Credit
Debt Instrument [Line Items]
Long-term debt	$ 316.9	$ 268.7

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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

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