Debt - Schedule of Debt and Capital Lease Obligations (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Current portion of finance lease	$ 0.1	$ 0.1
Current portion of debt	0.1	0.1
Long-term debt	805.1	699.4
Non-current portion of finance lease and other debt	1.7	1.7
Total debt	805.2	699.5
Senior unsecured credit facility
Debt Instrument [Line Items]
Long-term debt	105.0	0.0
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	(0.5)	(0.7)
Senior notes --- deferred financing costs	(1.1)	(1.6)
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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Amount of short-term and long-term debt and lease obligation.

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

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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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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