Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Currently payable
Federal		$ 2.1	$ 3.0	$ 0.0
International	[1]	109.2	101.7	88.5
Total current taxes		111.3	104.7	88.5
Deferred
International	[1]	(4.3)	(11.4)	(92.5)
Total deferred taxes		(4.3)	(11.4)	(92.5)
Total provision (benefit) for income taxes		$ 107.0	$ 93.3	$ (4.0)

[1] “Federal” represents U.K. taxes. (2) “International” represents non-U.K. taxes.