Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Decrease in Income Tax Expenses Unrecognized Tax Benefits if Recognized Net of Federal Tax	$ 2.8	$ 2.8
Effective Income Tax Rate Reconciliation, Percent		32.00%	33.00%
Deferred Tax Assets
Net deferred tax liabilities	1,157.7	$ 1,157.7		$ 1,089.4
Gross liability for unrecognized tax benefits
Effective Income Tax Rate Reconciliation, Change in State Enacted Tax Rate, Amount	$ 0.0