Debt - Carrying Amounts of Debt (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Unamortized discount and issuance costs	$ (3.2)	$ (20.0)
Total debt	381.8	358.7
Less: Current maturities	(16.3)	(2.7)
Total long-term debt	365.5	356.0
Line of Credit \| Senior Term Loan
Debt Instrument [Line Items]
Long-term Debt	325.0	268.7
Notes (primarily with related parties) \| Subordinated Notes Due 2026
Debt Instrument [Line Items]
Long-term Debt	$ 0.0	$ 110.0

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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