Long-term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
High yield notes	$ 315.0
Term loan	315.0
Unamortized debt issuance costs	(1.0)	$ (1.8)
Debt discount	(4.0)	(4.6)
Finance leases	11.6	1.5
Total debt and finance leases	321.6	144.3
Less: current maturities	(2.6)	(8.7)
Long-term debt and finance leases, net	$ 319.0	135.6
Term Loan
Debt Instrument [Line Items]
Term loan		$ 149.2

Debt instrument high yield notes.

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- Definition

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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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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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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