Debt and Credit Facilities - Summary of Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Debt Instrument
Total debt and credit facilities	$ 255.0	$ 290.0
Unsecured Senior Notes
Debt Instrument
Frequency of payments	semiannual
Weighted-average interest rate	4.21%	3.68%
Total principal outstanding	$ 185.0	$ 185.0
Current maturities	(135.0)	(100.0)
Long-term debt	$ 120.0	190.0
Unsecured Senior Notes \| Minimum
Debt Instrument
Maturity year	2024
Unsecured Senior Notes \| Maximum
Debt Instrument
Maturity year	2028
Credit Facility
Debt Instrument
Total principal outstanding	$ 0.0	$ 45.0
Debt, Weighted Average Interest Rate	6.43%	6.43%
Receivables Purchase Agreement
Debt Instrument
Total principal outstanding	$ 70.0
Short-Term Debt		$ 60.0
Debt, Weighted Average Interest Rate	6.29%	6.28%

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