Debt - Schedule of Debt and Capital Lease Obligations (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Current portion of finance lease	$ 0.9	$ 0.9
Current portion of debt	0.9	0.9
Long-term debt	876.4	925.5
Non-current portion of finance lease and other debt	1.7	2.5
Total debt	877.3	926.4
Senior unsecured credit facility
Debt Instrument [Line Items]
Long-term debt	179.0	228.0
4.7% senior notes due 2025
Debt Instrument [Line Items]
Senior notes	300.0	300.0
4.7% senior notes due 2025 and 3.95% senior notes due 2027
Debt Instrument [Line Items]
Senior notes --- original issue discount	(1.3)	(1.5)
Senior notes --- deferred financing costs	(3.0)	(3.5)
3.95% senior notes due 2027
Debt Instrument [Line Items]
Senior notes	$ 400.0	$ 400.0

Finance lease obligations noncurrent and other long term debt.

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- Definition

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

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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- Definition

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.

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

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), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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