Earnings per Common Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Earnings Per Share, Basic and Diluted [Line Items]
Net income	$ 71.4	$ 55.5	$ 193.3	$ 173.9
Weighted average common shares outstanding for basic earnings per share computation (in shares)	103,153,579	102,970,851	103,169,158	102,917,610
Dilutive effects of stock-based compensation (in shares)	233,412	262,767	235,643	207,449
Weighted average common shares outstanding for diluted earnings per common share computation (in shares)	103,386,991	103,233,618	103,404,801	103,125,059
Basic earnings per common share (in dollars per share)	$ 0.69	$ 0.54	$ 1.87	$ 1.69
Diluted earnings per common share (in dollars per share)	$ 0.69	$ 0.54	$ 1.87	$ 1.69
Restricted Stock
Earnings Per Share, Basic and Diluted [Line Items]
Anti-dilutive unvested time restricted stock (in shares)	4,135	5,841	6,014	47,854
Unvested restricted stock
Earnings Per Share, Basic and Diluted [Line Items]
Anti-dilutive unvested time restricted stock (in shares)			768,247	773,563

Earnings Per Share, Basic and Diluted [Line Items]

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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