Retirement Plans - Components of Estimated Net Periodic Benefit Income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 11.1	$ 11.7	$ 7.4
Expected return on assets	(13.5)	(13.2)	(11.6)
Amortization, net	1.3	1.0	3.3
Net pension plan income	$ (1.1)	$ (0.5)	$ (0.9)
Weighted-average assumptions used to calculate net pension plan income:
Discount rate	5.00%	5.20%	2.90%
Expected return on plan assets	6.00%	5.80%	4.80%