Employee Benefit Plans (Plans' Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in plan assets:
Fair value of plan assets at beginning of year	$ 291.0
Fair value of plan assets at end of year	154.3	$ 291.0
Pension Benefits [Member]
Pension and Postretirement Benefit Plans recognized in financial statements
Accumulated benefit obligation	237.3	368.0
Changes in projected benefit obligation:
Benefit obligation at beginning of year	371.9	405.5
Service cost	4.9	5.3	$ 5.0
Interest cost	10.2	12.3	12.6
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Other Change	0.0	0.3
Actuarial (gain) loss	38.9	(26.4)
Effect of exchange rates	1.1	(2.7)
Settlements and curtailments	(173.5)	(1.3)
Benefits paid	(12.0)	(21.1)
Benefit obligation at end of year	241.5	371.9	405.5
Changes in plan assets:
Fair value of plan assets at beginning of year	291.0	318.6
Actual gain return on plan assets	45.7	(23.3)
Employer contribution	1.8	20.6
Effect of exchange rates	1.3	(2.5)
Plan settlements	(173.5)	(1.3)
Benefits paid	(12.0)	(21.1)
Fair value of plan assets at end of year	154.3	291.0	$ 318.6
Funded status / net amount recognized	(87.2)	(80.9)
Net amount recognized consists of:
Non-current assets	3.5	3.3
Current liability	(3.3)	(1.4)
Non-current liability	(87.4)	(82.8)
Net amount recognized	$ (87.2)	$ (80.9)