Employee Benefit Plans (Schedule of Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Service cost	$ 6.0	$ 6.3	$ 7.8
Employee contributions	(1.4)	(1.3)	(1.5)
Amortization of prior service costs	(0.2)	(0.3)	(0.4)
Curtailment	0.0	(0.8)	(1.1)
Amortization and deferral of actuarial gain	0.2	0.5	0.8
Other	(0.2)	(0.3)	(0.6)
Total net periodic benefit cost	$ 4.4	$ 4.1	$ 5.0