Employee Benefit Plans (Plans' Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in plan assets:
Fair value of plan assets at beginning of year	$ 154.3
Fair value of plan assets at end of year	179.7	$ 154.3
Pension Benefits [Member]
Pension and Postretirement Benefit Plans recognized in financial statements
Accumulated benefit obligation	273.2	237.3
Changes in projected benefit obligation:
Benefit obligation at beginning of year	241.5	371.9
Service cost	5.5	4.9	$ 5.3
Interest cost	6.6	10.2	12.3
Amendments	(0.1)	0.0
Actuarial (gain) loss	27.2	38.9
Effect of exchange rates	2.2	1.1
Settlements and curtailments	(1.3)	(173.5)
Benefits paid	(5.6)	(12.0)
Benefit obligation at end of year	276.2	241.5	371.9
Changes in plan assets:
Fair value of plan assets at beginning of year	154.3	291.0
Actual gain return on plan assets	27.3	45.7
Employer contribution	3.4	1.8
Effect of exchange rates	1.6	1.3
Plan settlements	(1.3)	(173.5)
Benefits paid	(5.6)	(12.0)
Fair value of plan assets at end of year	179.7	154.3	$ 291.0
Funded status / net amount recognized	(96.5)	(87.2)
Net amount recognized consists of:
Non-current assets	5.0	3.5
Current liability	(9.0)	(3.3)
Non-current liability	(92.5)	(87.4)
Net amount recognized	$ (96.5)	$ (87.2)