Retirement and Deferred Compensation Plans - Reconciliation of Changes in Benefit Obligations and the Statement of Funded Status of Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension plans
Change in Benefit Obligation
Service cost	$ 15.1	$ 10.9	$ 10.1
Interest cost	12.7	11.6	10.6
Pension plans | United States Plans
Change in Benefit Obligation
Benefit obligation, beginning of year	48.9	53.7
Interest cost	1.8	1.6
Actuarial loss (gain)	6.3	(2.0)
Benefits paid	(4.2)	(4.4)
Benefit obligation, end of year	52.8	48.9	53.7
Change in Plan Assets
Fair value of plan assets, beginning of year	36.1	38.7
Actual return on plan assets	4.4	(0.7)
Company contributions	2.5	2.5
Benefits paid	(4.2)	(4.4)
Fair value of plan assets, end of year	38.8	36.1	38.7
Funded Status at End of Year
Funded status, end of year	(14.0)	(12.8)
Amounts Recognized
Noncurrent assets	15.0	15.0
Current liabilities	(2.5)	(2.5)
Noncurrent liabilities	(26.5)	(25.3)
Net amount recognized	(14.0)	(12.8)
Pension plans | Non-United States Plans
Change in Benefit Obligation
Benefit obligation, beginning of year	450.0	489.5
Service cost	15.1	10.9
Interest cost	10.9	10.0
Acquisitions	201.2
Settlements	(40.9)
Transfers	52.7	1.2
Actuarial loss (gain)	100.1	(28.0)
Plan participant contributions	9.0	0.2
Benefits paid	(11.3)	(10.5)
Currency exchange rate changes	8.0	(23.3)
Benefit obligation, end of year	794.8	450.0	489.5
Change in Plan Assets
Fair value of plan assets, beginning of year	354.1	376.7
Actual return on plan assets	69.5	(2.4)
Acquisitions	196.8
Settlements	(40.9)
Transfers	51.6	(0.3)
Plan participant contributions	9.0	0.2
Company contributions	15.4	9.2
Benefits paid	(11.3)	(10.5)
Currency exchange rate changes	11.2	(18.8)
Fair value of plan assets, end of year	655.4	354.1	376.7
Funded Status at End of Year
Funded status, end of year	(139.4)	(95.9)
Amounts Recognized
Noncurrent assets	41.4	46.9
Current liabilities	(0.7)	(0.5)
Noncurrent liabilities	(180.1)	(142.3)
Net amount recognized	(139.4)	(95.9)
Retiree health care plan
Change in Benefit Obligation
Benefit obligation, beginning of year	13.7	14.9
Interest cost	0.5	0.5	0.6
Actuarial loss (gain)	0.8	(0.5)
Benefits paid	(0.9)	(1.2)
Benefit obligation, end of year	14.1	13.7	$ 14.9
Funded Status at End of Year
Funded status, end of year	(14.1)	(13.7)
Amounts Recognized
Current liabilities	(1.1)	(1.1)
Noncurrent liabilities	(13.0)	(12.6)
Net amount recognized	$ (14.1)	$ (13.7)