Pension Plans - Funded Status of Non-U.S. Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
U.S. Pension Benefits
Change in pension benefit obligation:
Benefit obligation at beginning of year	$ 33.7	$ 0.0
Service cost	0.0	0.0
Interest cost	1.2	0.3
Employee contributions	0.0	0.0
Benefits paid and other	(1.3)	(0.2)
Plan combinations/acquisitions	0.0	33.1
Actuarial loss (gain)	(2.7)	0.5
Amendments, settlements and curtailments	0.0	0.0
Foreign exchange rate impact	0.0	0.0
Benefit obligation at end of year	30.9	33.7	$ 0.0
Change in plan assets:
Fair value of plan assets at beginning of year	25.8	0.0
Actual return on plan assets	(1.2)	0.5
Employer contributions	0.0	0.0
Employee contributions	0.0	0.0
Amendments and settlements	0.0	0.0
Benefits paid and other	(1.3)	(0.2)
Plan combinations/acquisitions	0.0	25.5
Foreign exchange rate impact	0.0	0.0
Fair value of plan assets at end of year	23.3	25.8	0.0
Funded status	(7.6)	(7.9)
Non-U.S. Pension Benefits
Change in pension benefit obligation:
Benefit obligation at beginning of year	300.8	292.3
Service cost	1.3	3.5	3.1
Interest cost	5.7	5.8	7.2
Employee contributions	0.2	1.3
Benefits paid and other	(9.5)	(9.3)
Plan combinations/acquisitions	0.0	1.5
Actuarial loss (gain)	(7.0)	(10.8)
Amendments, settlements and curtailments	(3.0)	(17.6)
Foreign exchange rate impact	(14.2)	34.1
Benefit obligation at end of year	274.3	300.8	292.3
Change in plan assets:
Fair value of plan assets at beginning of year	172.2	164.2
Actual return on plan assets	(3.1)	(8.3)
Employer contributions	9.8	10.4
Employee contributions	0.2	1.3
Amendments and settlements	(4.4)	(5.1)
Benefits paid and other	(9.5)	(9.3)
Plan combinations/acquisitions	0.0	0.9
Foreign exchange rate impact	(8.7)	18.1
Fair value of plan assets at end of year	156.5	172.2	$ 164.2
Funded status	$ (117.8)	$ (128.6)