Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Nov. 22, 2019
Debt Instrument [Line Items]
Senior Notes	$ 550.0	$ 550.0	$ 550.0
Long-term Debt, Gross	1,040.8	1,040.8
Unamortized Debt Issuance Expense	6.6	6.9
Long-term debt	1,034.2	1,033.9
$490.8 Million Term B Loan Facility, due April 2025
Debt Instrument [Line Items]
Secured Debt	$ 490.8	$ 490.8

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 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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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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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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