Financing Arrangements - Long-term debt (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Financing Arrangements
Less debt issuance costs (deduction from debt liability)	$ (2.3)	$ (3.0)
Total long-term debt	197.7	197.0
Principal payments during each of the next five years and thereafter
2026	0.0
2027	0.0
2028	0.0
2029	200.0
2030	0.0
Line of Credit due July 2029
Financing Arrangements
Total debt	$ 200.0	$ 200.0

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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