Pension, Post-Retirement and Post-Employment Plans - Changes in Funded Status of Pension and SERP Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change in Plan Assets:
Beginning of period balance	$ 189.0
End of period balance	211.9	$ 189.0
Pension Plan and SERP | Domestic
Change in Projected Benefit Obligation:
Beginning of period balance	206.2	226.2
Additions	0.0	0.0
Service cost	0.0	0.0	$ 0.0
Plan amendments	0.0	0.0
Interest cost	8.7	8.1	8.8
Actuarial loss (gain) due to assumption change	25.6	(15.4)
Actuarial (gain) loss due to plan experience	(1.1)	(1.7)
Benefits and expenses paid	(11.5)	(10.3)
Settlement	0.0	(0.7)
Foreign currency translation	0.0	0.0
End of period balance	227.9	206.2	226.2
Change in Plan Assets:
Beginning of period balance	184.7	199.6
Additions	0.0	0.0
Actual return on plan assets, net of expenses	32.2	(5.1)
Employer contributions	0.5	1.2
Benefits paid	(11.5)	(10.3)
Settlement	0.0	(0.7)
Foreign currency translation	0.0	0.0
End of period balance	205.9	184.7	199.6
Funded Status
Funded status of plan	(22.0)	(21.5)
Supplemental Information:
Accumulated benefit obligation	217.1	196.8
Plans with Accumulated Benefit Obligation in excess of Plan Assets:
Accumulated benefit obligation	217.1	196.8
Fair value plan assets	205.9	184.7
Plans with Projected Benefit Obligation in excess of Plan Assets:
Projected benefit obligation	227.9	206.2
Fair value plan assets	205.9	184.7
Pension Plan and SERP | Foreign
Change in Projected Benefit Obligation:
Beginning of period balance	23.3	23.0
Additions	2.7	2.0
Service cost	0.7	1.2	1.6
Plan amendments	0.0	0.0
Interest cost	0.3	0.3	1.4
Actuarial loss (gain) due to assumption change	1.1	(0.5)
Actuarial (gain) loss due to plan experience	1.0	0.2
Benefits and expenses paid	(0.6)	(0.9)
Settlement	(1.6)	(1.1)
Foreign currency translation	(0.2)	(0.9)
End of period balance		23.3	23.0
Change in Plan Assets:
Beginning of period balance	4.3	7.7
Additions	0.0	0.0
Actual return on plan assets, net of expenses	1.4	0.2
Employer contributions	2.4	(1.7)
Benefits paid	(0.6)	(0.9)
Settlement	(1.6)	(0.8)
Foreign currency translation	0.1	(0.2)
End of period balance	6.0	4.3	7.7
Funded Status
Funded status of plan	(20.6)	(19.0)
Supplemental Information:
Accumulated benefit obligation	23.3	20.1
Plans with Accumulated Benefit Obligation in excess of Plan Assets:
Accumulated benefit obligation	23.2	20.0
Fair value plan assets	5.8	4.1
Plans with Projected Benefit Obligation in excess of Plan Assets:
Projected benefit obligation	26.5	23.1
Fair value plan assets	5.8	4.1
Post-retirement Medical Benefits | Domestic
Change in Projected Benefit Obligation:
Beginning of period balance	9.0	9.7
Additions	0.0	0.0
Service cost	0.0	0.0	0.0
Plan amendments	0.0	0.0
Interest cost	0.4	0.4	0.4
Actuarial loss (gain) due to assumption change	1.0	(1.1)
Actuarial (gain) loss due to plan experience	(0.6)	0.5
Benefits and expenses paid	(0.6)	(0.5)
Settlement	0.0	0.0
Foreign currency translation	0.0	0.0
End of period balance	9.2	9.0	9.7
Change in Plan Assets:
Beginning of period balance	0.0	0.0
Additions	0.0	0.0
Actual return on plan assets, net of expenses	0.0	0.0
Employer contributions	0.5	0.5
Benefits paid	(0.5)	(0.5)
Settlement	0.0	0.0
Foreign currency translation	0.0	0.0
End of period balance	0.0	0.0	0.0
Funded Status
Funded status of plan	(9.2)	(9.0)
Supplemental Information:
Accumulated benefit obligation	9.2	9.0
Plans with Accumulated Benefit Obligation in excess of Plan Assets:
Accumulated benefit obligation	9.2	9.0
Fair value plan assets	0.0	0.0
Plans with Projected Benefit Obligation in excess of Plan Assets:
Projected benefit obligation	9.2	9.0
Fair value plan assets	0.0	0.0
Post-retirement Medical Benefits | Foreign
Change in Projected Benefit Obligation:
Beginning of period balance	1.3	0.9
Additions	0.0	0.0
Service cost	0.1	0.1	0.0
Plan amendments	(1.4)	0.0
Interest cost	0.1	0.1	0.1
Actuarial loss (gain) due to assumption change	0.1	0.1
Actuarial (gain) loss due to plan experience	(0.1)	0.3
Benefits and expenses paid	0.0	0.0
Settlement	0.0	0.0
Foreign currency translation	0.0	(0.2)
End of period balance	0.1	1.3	0.9
Change in Plan Assets:
Beginning of period balance	0.0	0.0
Additions	0.0	0.0
Actual return on plan assets, net of expenses	0.0	0.0
Employer contributions	0.0	0.0
Benefits paid	0.0	0.0
Settlement	0.0	0.0
Foreign currency translation	0.0	0.0
End of period balance	0.0	0.0	$ 0.0
Funded Status
Funded status of plan	(0.1)	(1.3)
Supplemental Information:
Accumulated benefit obligation	0.1	1.3
Plans with Accumulated Benefit Obligation in excess of Plan Assets:
Accumulated benefit obligation	0.1	1.3
Fair value plan assets	0.0	0.0
Plans with Projected Benefit Obligation in excess of Plan Assets:
Projected benefit obligation	0.1	1.3
Fair value plan assets	$ 0.0	$ 0.0