Retirement Plans, Postretirement and Postemployment Benefits - Schedule of Amounts Recognized on Consolidated Balance Sheet (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Noncurrent asset pension and postretirement benefits	$ 307.8	$ 295.3
Current pension and postretirement benefits	(7.5)	(6.8)
Noncurrent pension, postretirement and postemployment benefits	(92.7)	(79.0)
Net amount recognized at end of year	207.6	209.5
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized at end of year	(8.3)	(8.9)
Current pension and postretirement benefits	(1.0)	(1.0)
Noncurrent pension, postretirement and postemployment benefits	(7.3)	(7.9)
Net amount recognized at end of year	$ (8.3)	$ (8.9)