Earnings per Common Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Earnings Per Share, Basic and Diluted [Line Items]
Net income	$ 71.7	$ 60.0	$ 121.9	$ 118.4
Weighted average common shares outstanding for basic earnings per share computation (in shares)	103,260,996	102,936,996	103,177,077	102,890,697
Dilutive effects of stock-based compensation (in shares)	102,696	156,139	226,986	184,746
Weighted average common shares outstanding for diluted earnings per common share computation (in shares)	103,363,692	103,093,135	103,404,063	103,075,443
Basic earnings per common share (in dollars per share)	$ 0.69	$ 0.58	$ 1.18	$ 1.15
Diluted earnings per common share (in dollars per share)	$ 0.69	$ 0.58	$ 1.18	$ 1.15
Restricted Stock
Earnings Per Share, Basic and Diluted [Line Items]
Anti-dilutive unvested time restricted stock (in shares)	428,989	55,785	915	55,953
Unvested restricted stock
Earnings Per Share, Basic and Diluted [Line Items]
Anti-dilutive unvested time restricted stock (in shares)			798,491	786,790

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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