Long-term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
High yield notes	$ 315.0
Unamortized debt issuance costs	(1.1)	$ (1.8)
Debt discount	(4.2)	(4.6)
Capital leases	0.8	1.5
Total debt and capital leases	310.5	144.3
Less: current maturities	(0.6)	(8.7)
Long-term debt and capital leases, net	$ 309.9	135.6
Term Loan
Debt Instrument [Line Items]
Term loan		$ 149.2

Debt instrument high yield notes.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of short-term and long-term debt and lease obligation.

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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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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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Amount, after accumulated amortization, of debt discount.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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