Income Taxes (Provision for Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 55.9	$ 59.5	$ 86.1
State	14.2	17.8	12.5
Foreign	9.3	4.6	15.0
Total current	79.4	81.9	113.6
Deferred:
Federal	15.0	23.2	43.8
State	3.9	1.0	0.9
Foreign	0.8	1.5	(1.4)
Total deferred	19.7	25.7	43.3
Total provision for income taxes	$ 99.1	$ 107.6	$ 156.9