Schedule of U.S. Federal, State and Foreign Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
U.S. federal	$ 183.4	$ 161.4	$ 159.0
State, Current	27.2	25.5	24.4
Foreign, Current	11.4	14.1	14.9
Current income tax expense (benefit)	222.0	201.0	198.3
U.S. federal, Deferred	19.2	22.8	11.5
State, Deferred	4.1	3.3	1.1
Foreign, Deferred	1.6	(2.1)	0.1
Deferred income tax expense (benefit)	24.9	24.0	12.7
Recorded tax expense	$ 246.9	$ 225.0	$ 211.0