Pension and Other Postretirement Benefits - Benefit Plan Obligations, Plan Assets, Funded Status, and Net Liability Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Change in Benefit Obligation:
Plan curtailment	$ (0.1)
Amounts recognized in statement of financial position consist of:
Noncurrent liabilities					$ (93.1)	$ (92.9)
Curtailment gain	1.6
Pension Benefits
Change in Benefit Obligation:
Benefit obligation at beginning of year		$ 430.7	$ 463.9
Service cost		5.0	6.7	$ 5.5
Interest cost		16.2	15.8	15.0
Currency		(1.2)	(4.6)
Actuarial (gain) loss		55.0	(29.3)
Benefit payments from plans		(21.1)	(20.3)
Plan curtailment		(2.8)	0.0
Settlement payments		(0.5)	(2.2)
Other		1.1	0.7
Benefit obligation at end of year	482.4	482.4	430.7	463.9
Change in Plan Assets:
Fair value of plan assets at beginning of year		375.2	400.4
Actual gain (loss) on plan assets		62.1	(18.9)
Employer contributions		8.3	18.2
Currency		(0.5)	(2.7)
Benefit payments		(21.1)	(20.3)
Settlement payments		(0.5)	(2.2)
Other		0.6	0.7
Fair value of plan assets at end of year	424.1	424.1	375.2	400.4
Reconciliation of Funded Status
Fair value of plan assets	424.1	424.1	400.4	400.4	424.1	375.2
Projected benefit obligation	482.4	430.7	430.7	463.9	482.4	430.7
Net liability recognized in statement of financial position					(58.3)	(55.5)
Amounts recognized in statement of financial position consist of:
Current liabilities					(1.2)	(1.7)
Noncurrent liabilities					(57.1)	(53.8)
Net amount recognized					(58.3)	(55.5)
Curtailment gain		1.6	0.0	0.0
Postretirement Benefits Other than Pensions
Change in Benefit Obligation:
Benefit obligation at beginning of year		42.4	44.0
Service cost		1.2	1.1	1.2
Interest cost		1.5	1.4	1.4
Currency		0.1	(0.3)
Actuarial (gain) loss		(0.7)	1.1
Benefit payments from plans		(4.8)	(4.9)
Plan curtailment		0.0	0.0
Settlement payments		0.0	0.0
Other		0.0	0.0
Benefit obligation at end of year	39.7	39.7	42.4	44.0
Change in Plan Assets:
Fair value of plan assets at beginning of year		0.0	0.0
Actual gain (loss) on plan assets		0.0	0.0
Employer contributions		0.0	0.0
Currency		0.0	0.0
Benefit payments		0.0	0.0
Settlement payments		0.0	0.0
Other		0.0	0.0
Fair value of plan assets at end of year	0.0	0.0	0.0	0.0
Reconciliation of Funded Status
Fair value of plan assets	0.0	0.0	0.0	0.0	0.0	0.0
Projected benefit obligation	39.7	42.4	42.4	44.0	39.7	42.4
Net liability recognized in statement of financial position					(39.7)	(42.4)
Amounts recognized in statement of financial position consist of:
Current liabilities					(5.6)	(5.2)
Noncurrent liabilities					(34.1)	(37.2)
Net amount recognized					$ (39.7)	$ (42.4)
Curtailment gain		0.0	$ 0.0	0.0
Level 3 | Insurance Contracts Acquired in Business Combination | W.A. Sanders Coldenhove Holding B.V.
Amounts recognized in statement of financial position consist of:
Net Purchases/ (Settlements)				$ 46.8
Netherlands | Dutch Defined Benefit Plan | Pension Benefits
Amounts recognized in statement of financial position consist of:
Curtailment gain	$ 1.6	$ 1.6