Post-Employment Plans - Projected Benefit Obligation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	$ 134.6
Fair value of plan assets at end of period	150.4	$ 134.6
Pension Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of period	127.5	202.6
Net acquisitions/(disposals)	0.0	(1.3)
Service costs	2.9	3.3	$ 3.9
Interest cost	5.2	2.7	2.6
Actuarial loss (gain)	14.4	(64.7)
Curtailment	(0.6)	0.0
Contributions paid	0.3	0.3
Benefits paid	(2.7)	(1.5)
Settlements	(0.7)	(1.7)
Foreign currency translation	4.9	(12.2)
Projected benefit obligation at end of period	151.2	127.5	202.6
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	134.6	181.7
Net acquisitions/(disposals)	0.0	(1.1)
Actual return on plan assets	11.7	(34.2)
Benefits paid	(2.7)	(1.5)
Settlements	(0.7)	(1.7)
Employer contributions	2.5	2.3
Contributions paid	0.3	0.3
Foreign currency translation	4.7	(11.2)
Fair value of plan assets at end of period	150.4	134.6	181.7
Funded/(unfunded) status	(0.8)	7.1
Pension Benefits | Other non-current assets
Change in Fair Value of Plan Assets [Roll Forward]
Funded/(unfunded) status	27.7	32.4
Pension Benefits | Other non-current liabilities
Change in Fair Value of Plan Assets [Roll Forward]
Funded/(unfunded) status	(28.5)	(25.3)
Other Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of period	2.0	3.0
Net acquisitions/(disposals)	0.0	0.0
Service costs	0.0	0.0	0.0
Interest cost	0.1	0.1	0.1
Actuarial loss (gain)	(0.2)	(1.0)
Curtailment	0.0	0.0
Contributions paid	0.0	0.0
Benefits paid	(0.1)	(0.1)
Settlements	0.0	0.0
Foreign currency translation	0.0	0.0
Projected benefit obligation at end of period	1.8	2.0	3.0
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	0.0	0.0
Net acquisitions/(disposals)	0.0	0.0
Actual return on plan assets	0.0	0.0
Benefits paid	(0.1)	(0.1)
Settlements	0.0	0.0
Employer contributions	0.1	0.1
Contributions paid	0.0	0.0
Foreign currency translation	0.0	0.0
Fair value of plan assets at end of period	0.0	0.0	$ 0.0
Funded/(unfunded) status	(1.8)	(2.0)
Other Benefits | Other non-current assets
Change in Fair Value of Plan Assets [Roll Forward]
Funded/(unfunded) status	0.0	0.0
Other Benefits | Other non-current liabilities
Change in Fair Value of Plan Assets [Roll Forward]
Funded/(unfunded) status	$ (1.8)	$ (2.0)