Benefit Plans Benefit Plans - Summary of Benefit Plan (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Change in accumulated other comprehensive income
Acquired benefit plans and other		$ (0.2)	$ 3.2	$ 7.7
Pension Benefits
Change in plan assets
Employer contributions		27.8
Other Benefits
Change in benefit obligation
Benefit obligation at beginning of year		17.1	15.3
Service cost		0.1	0.1	0.0
Interest cost		0.8	1.0	0.4
Actuarial loss (gain)		1.3	(1.8)
Plan participant contributions		0.0	0.0
Benefits paid		(0.7)	(0.8)
Plan amendments		0.0	0.0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment		0.0	0.0
Settlements		0.0	0.0
Recognition/establishment of Germany benefit obligation		0.0	0.0	0.0
Foreign currency impact		(2.3)	(0.3)
Acquired benefit plans and other		0.0	0.0
Benefit obligation at end of year		13.7	17.1	15.3
Change in plan assets
Fair value of plan assets at beginning of year		0.0	0.0
Actual return on plan assets		0.0	0.0
Employer contributions		0.7	0.8
Plan participant contributions		0.0	0.0
Benefits paid		(0.7)	(0.8)
Foreign currency impact		0.0	0.0
Defined Benefit Plan Acquisitions and Other Plan Assets		0.0	0.0
Settlements		0.0	0.0
Fair value of plan assets at end of year		0.0	0.0	0.0
Funded status		(13.7)	(17.1)
Amounts recognized in balance sheets
Assets for Plan Benefits, Defined Benefit Plan		0.0	0.0
Current liabilities		0.9	1.0
Noncurrent liabilities	[1]	12.9	16.1
Unrecognized net actuarial loss	[2]	(3.8)	(7.4)
Unrecognized prior service cost (benefit)	[2]	0.0	0.0
Net amount recognized		10.0	9.7
Change in accumulated other comprehensive income
Balance at beginning of year		(7.5)	(6.3)
Prior service credit/loss recognized during the year		0.0	0.0
Net actuarial gains (losses) recognized during the year		0.4	0.4
Net actuarial (losses) gains occurring during the year		1.3	(1.9)
Net actuarial losses recognized due to settlement		0.0	0.0
Acquired benefit plans and other		0.0	0.0
Foreign currency impact		2.0	0.3
Balance at end of year		(3.8)	(7.5)	(6.3)
United States | Pension Benefits
Change in benefit obligation
Benefit obligation at beginning of year		580.0	522.2
Service cost		3.8	3.7	3.9
Interest cost		18.9	22.1	20.6
Actuarial loss (gain)		47.7	62.5
Plan participant contributions		0.0	0.0
Benefits paid		(30.3)	(30.5)
Plan amendments		0.0	0.0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment		0.0	0.0
Settlements		0.0	0.0
Recognition/establishment of Germany benefit obligation		0.0	0.0	0.0
Foreign currency impact		0.0	0.0
Acquired benefit plans and other		0.0	0.0
Benefit obligation at end of year		620.1	580.0	522.2
Change in plan assets
Fair value of plan assets at beginning of year		427.8	346.0
Actual return on plan assets		70.2	74.1
Employer contributions		18.7	38.1
Plan participant contributions		0.0	0.0
Benefits paid		(30.3)	(30.4)
Foreign currency impact		0.0	0.0
Defined Benefit Plan Acquisitions and Other Plan Assets		0.0	0.0
Settlements		0.0	0.0
Fair value of plan assets at end of year		486.4	427.8	346.0
Funded status		(133.7)	(152.2)
Amounts recognized in balance sheets
Assets for Plan Benefits, Defined Benefit Plan		2.7	1.4
Current liabilities		3.5	3.5
Noncurrent liabilities	[1]	132.9	150.1
Unrecognized net actuarial loss	[2]	(154.4)	(159.2)
Unrecognized prior service cost (benefit)	[2]	0.0	0.0
Net amount recognized		(20.7)	(7.0)
Change in accumulated other comprehensive income
Balance at beginning of year		(159.4)	(151.4)
Prior service credit/loss recognized during the year		0.0	0.0
Net actuarial gains (losses) recognized during the year		7.8	5.1
Net actuarial (losses) gains occurring during the year		(2.9)	(13.1)
Net actuarial losses recognized due to settlement		0.0	0.0
Acquired benefit plans and other		0.0	0.0
Foreign currency impact		0.0	0.0
Balance at end of year		(154.5)	(159.4)	(151.4)
Foreign Plan [Member] | Pension Benefits
Change in benefit obligation
Benefit obligation at beginning of year		456.1	426.5
Service cost		9.8	9.8	11.0
Interest cost		4.0	6.5	6.2
Actuarial loss (gain)		(14.6)	(32.7)
Plan participant contributions		1.4	1.3
Benefits paid		(21.7)	(17.5)
Plan amendments		2.1	0.4
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment		(1.1)	0.0
Settlements		(0.7)	(5.8)
Recognition/establishment of Germany benefit obligation		0.0	7.1	0.0
Foreign currency impact		37.6	(3.4)
Acquired benefit plans and other		(33.4)	(1.5)
Benefit obligation at end of year		468.7	456.1	426.5
Change in plan assets
Fair value of plan assets at beginning of year		359.6	340.9
Actual return on plan assets		15.0	37.3
Employer contributions		8.4	6.9
Plan participant contributions		1.4	1.3
Benefits paid		(21.7)	(17.5)
Foreign currency impact		32.1	(3.3)
Defined Benefit Plan Acquisitions and Other Plan Assets		0.0	(0.2)
Settlements		(0.7)	(5.8)
Fair value of plan assets at end of year		394.1	359.6	340.9
Funded status		(74.6)	(96.5)
Amounts recognized in balance sheets
Assets for Plan Benefits, Defined Benefit Plan		0.0	0.0
Current liabilities		11.5	8.2
Noncurrent liabilities	[1]	63.1	88.3
Unrecognized net actuarial loss	[2]	(4.9)	6.2
Unrecognized prior service cost (benefit)	[2]	1.1	0.3
Net amount recognized		70.8	103.0
Change in accumulated other comprehensive income
Balance at beginning of year		6.5	19.8
Prior service credit/loss recognized during the year		0.7	(0.5)
Net actuarial gains (losses) recognized during the year		(0.6)	(1.5)
Net actuarial (losses) gains occurring during the year		(12.0)	(7.7)
Net actuarial losses recognized due to settlement		1.1	(0.9)
Acquired benefit plans and other		0.2	(2.8)
Foreign currency impact		0.3	0.1
Balance at end of year		$ (3.8)	$ 6.5	$ 19.8

[1] Included in the consolidated balance sheets in pensions, post-retirement and other benefits

[2] Represents amounts in accumulated other comprehensive loss that have not yet been recognized as components of net periodic benefit cost.