Retirement Benefit Plan - Changes in Fair Value of Plan Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
U.S. and Puerto Rico [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Plan assets at fair market value - beginning of year	$ 444.9	$ 388.5
Actual return on plan assets	51.4	73.5
Employer contributions	3.1	2.0
Settlements	(1.3)	(2.2)
Benefits paid	(24.0)	(16.9)
Plan assets at fair market value - end of year	474.1	444.9
Funded status	(42.8)	(27.1)
Foreign [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Plan assets at fair market value - beginning of year	665.2	585.8
Actual return on plan assets	40.0	57.8
Employer contributions	21.2	20.1
Employee contributions	22.1	20.6
Settlements	(4.5)
Benefits paid	(39.8)	(36.5)
Expenses paid	(0.3)	(0.3)
Translation gain	52.8	17.7
Plan assets at fair market value - end of year	756.7	665.2
Funded status	$ (62.6)	$ (75.2)