Employee Benefit Plans (Funded Status of Pension Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, beginning of year	$ 1,910.5		$ 2,178.1
Actual return on plan assets	172.1		142.0
Employer contributions	9.8		10.0
Currency translation adjustments	(3.5)		(7.0)
Benefits Paid	100.1		412.6
Fair Value of Plan Assets, end of year	1,988.8		1,910.5		$ 2,178.1
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	1,951.2		2,135.3
Service cost	59.7		59.8		74.6
Interest cost	61.8		78.6		65.4
Actuarial (gains)/losses	210.7		95.8
Currency translation adjustments	(3.6)		(8.7)
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	0.4		0.8
Curtailments and special termination benefits	22.0		(48.7)		(319.5)
Benefits Paid	(100.1)		(412.6)
Projected benefit obligation at end of year	2,180.1		1,951.2		2,135.3
Funded status - plan assets less benefit obligations	(191.3)		(40.7)
Defined Benefit Plan, Benefit Obligation, Payment for Settlement			(48.2)		$ (319.6)
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	$ 0.0		$ 2.2
Defined Contribution Plan, Cost		$ 112.7		$ 110.9		$ 100.6