Employee Benefit Plans (Plans' Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Changes in plan assets:
Fair value of plan assets at beginning of year	$ 293.0
Fair value of plan assets at end of year	292.5	$ 293.0
Pension Benefits [Member]
Pension and Postretirement Benefit Plans recognized in financial statements
Accumulated benefit obligation	374.1	409.2
Changes in projected benefit obligation:
Benefit obligation at beginning of year	415.4	446.5
Service cost	4.4	4.8	$ 4.2
Interest cost	15.3	17.2	17.7
Plan participants' contributions	0.0	0.0
Amendments	0.1	0.1
Other	0.0	0.0
Actuarial (gain) loss	22.8	(29.6)
Effect of exchange rates	(3.8)	(5.2)
Divestiture	0.0	0.0
Settlements and curtailments	(50.6)	(0.8)
Benefits paid	(22.0)	(17.6)
Benefit obligation at end of year	381.6	415.4	446.5
Changes in plan assets:
Fair value of plan assets at beginning of year	293.0	315.0
Actual gain return on plan assets	21.0	(3.2)
Employer contribution	53.9	3.8
Plan participants' contributions	0.0	0.0
Effect of exchange rates	(2.8)	(4.2)
Divestiture	0.0	0.0
Plan settlements	(50.6)	(0.8)
Benefits paid	(22.0)	(17.6)
Fair value of plan assets at end of year	292.5	293.0	315.0
Funded status / net amount recognized	(89.1)	(122.4)
Net amount recognized consists of:
Current liability	(1.6)	(1.6)
Non-current liability	(87.5)	(120.8)
Net amount recognized	(89.1)	(122.4)
Other Benefits [Member]
Changes in projected benefit obligation:
Benefit obligation at beginning of year	4.9	5.4
Service cost	0.0	0.0	0.0
Interest cost	0.1	0.2	0.2
Plan participants' contributions	0.3	0.5
Amendments	0.0	0.0
Other	0.0	0.0
Actuarial (gain) loss	(0.7)	0.1
Effect of exchange rates	0.0	0.0
Divestiture	0.0	0.0
Settlements and curtailments	0.0	0.0
Benefits paid	(1.3)	(1.3)
Benefit obligation at end of year	3.3	4.9	5.4
Changes in plan assets:
Fair value of plan assets at beginning of year	0.0	0.0
Actual gain return on plan assets	0.0	0.0
Employer contribution	1.0	0.8
Plan participants' contributions	0.3	0.5
Effect of exchange rates	0.0	0.0
Divestiture	0.0	0.0
Plan settlements	0.0	0.0
Benefits paid	(1.3)	(1.3)
Fair value of plan assets at end of year	0.0	0.0	$ 0.0
Funded status / net amount recognized	(3.3)	(4.9)
Net amount recognized consists of:
Current liability	(0.5)	(0.8)
Non-current liability	(2.8)	(4.1)
Net amount recognized	$ (3.3)	$ (4.9)