Defined contribution and defined benefit retirement plans - Schedule of Defined Benefit Pension Plans Balances (for which Accumulated Benefit Obligation Exceeds Fair Value of Plan Assets) (Detail) - Foreign Pension Plans Defined Benefit - Defined benefit pension plans - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Projected Benefit Obligation (PBO)	$ 463.1	$ 403.5
Accumulated Benefit Obligation (ABO)	452.9	392.4
Fair value of plan assets	$ 313.8	$ 276.0