Retirement Benefit Plans - Changes in Plan Assets and Benefit Obligations in AOCL (Details) - Accrued pension cost - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
U.S. Plans
Changes in prior service cost recognized in accumulated other comprehensive loss (income):
Accumulated other comprehensive income at beginning of year	$ 2.7	$ 4.8
Prior service cost	0.0	0.1
Recognized prior service cost	(1.2)	(1.6)
Loss recognized due to curtailment	0.0	(0.6)
Foreign currency impact	0.0	0.0
Accumulated other comprehensive income at ending of year	1.5	2.7
International Plans
Changes in prior service cost recognized in accumulated other comprehensive loss (income):
Accumulated other comprehensive income at beginning of year	3.9	3.9
Prior service cost	0.5	0.0
Recognized prior service cost	(0.2)	(0.2)
Loss recognized due to curtailment	0.0	0.0
Foreign currency impact	0.0	0.2
Accumulated other comprehensive income at ending of year	$ 4.2	$ 3.9