Net Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Net earnings	$ 82.0	$ 61.9
Distributed and allocated undistributed net earnings to unvested restricted stockholders	0.0	0.0
Net earnings available to common stockholders	$ 82.0	$ 61.9
Denominator:
Weighted average number of common shares outstanding - basic (in shares)	144.9	144.1
Basic net earnings per common share:
Basic net earnings per common share (in dollars per share)	$ 0.57	$ 0.43
Numerator:
Net earnings available to common stockholders	$ 82.0	$ 61.9
Denominator:
Weighted average number of common shares outstanding - basic (in shares)	144.9	144.1
Effect of unvested restricted stock units (in shares)	0.5	0.7
Weighted average number of common shares outstanding - diluted under treasury stock (in shares)	145.4	144.8
Diluted net earnings per common share (in dollars per share)	$ 0.56	$ 0.43