Retirement Plans, Postretirement and Postemployment Benefits - Schedule of Funded Status (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit credit (cost)	$ 64.8	$ (74.0)
Pension
Defined Benefit Plan Disclosure [Line Items]
Funded status of the plan at end of year	64.8	(74.0)
Accrued benefit credit (cost)	64.8	(74.0)
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Funded status of the plan at end of year	(11.4)	(12.6)
Accrued benefit credit (cost)	$ (11.4)	$ (12.6)