Benefit Plans - Reconciliation of Changes in Benefit Obligations and Fair Value of Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Fair Value of Plan Assets:
Beginning balance	$ 310.2
Fair value of plan assets ending balance	679.8	$ 310.2
Pension Benefits | U.S. Plans
Reconciliation of Benefit Obligations:
Beginning balance	59.8	57.4
Service cost	5.8	0.0	$ 0.0
Interest cost	9.5	2.2	2.1
Plan amendments	0.0	0.0
Actuarial losses (gains)	18.1	4.3
Benefit payments	(29.0)	(2.8)
Acquisitions	424.0	0.0
Plan settlements	(0.9)	(1.3)
Effect of foreign currency exchange rate changes	0.0	0.0
Benefit obligations ending balance	487.3	59.8	57.4
Reconciliation of Fair Value of Plan Assets:
Beginning balance	61.1	57.7
Actual return on plan assets	36.5	7.4
Employer contributions	0.1	0.1
Acquisitions	327.2	0.0
Plan settlements	(0.9)	(1.3)
Benefit payments	(29.0)	(2.8)
Effect of foreign currency exchange rate changes	0.0	0.0
Fair value of plan assets ending balance	395.0	61.1	57.7
Funded Status as of Period End	(92.3)	1.3
Pension Benefits | Non-U.S. Plans
Reconciliation of Benefit Obligations:
Beginning balance	346.5	304.9
Service cost	3.8	1.5	1.8
Interest cost	6.1	7.7	7.5
Plan amendments	0.0	0.0
Actuarial losses (gains)	24.4	35.9
Benefit payments	(12.8)	(10.3)
Acquisitions	56.7	0.0
Plan settlements	0.0	0.0
Effect of foreign currency exchange rate changes	21.0	6.8
Benefit obligations ending balance	445.7	346.5	304.9
Reconciliation of Fair Value of Plan Assets:
Beginning balance	249.1	212.2
Actual return on plan assets	19.0	35.3
Employer contributions	7.6	4.3
Acquisitions	12.0	0.0
Plan settlements	0.0	0.0
Benefit payments	(12.8)	(10.3)
Effect of foreign currency exchange rate changes	9.9	7.6
Fair value of plan assets ending balance	284.8	249.1	212.2
Funded Status as of Period End	(160.9)	(97.4)
Other Postretirement Benefits
Reconciliation of Benefit Obligations:
Beginning balance	3.4	3.1
Service cost	0.0	0.0	0.0
Interest cost	0.5	0.1	0.1
Plan amendments	(1.6)	0.0
Actuarial losses (gains)	2.0	0.4
Benefit payments	(2.7)	(0.2)
Acquisitions	29.5	0.0
Plan settlements	0.3	0.0
Effect of foreign currency exchange rate changes	0.1	0.0
Benefit obligations ending balance	31.5	3.4	$ 3.1
Reconciliation of Fair Value of Plan Assets:
Funded Status as of Period End	$ (31.5)	$ (3.4)