Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Contingency [Line Items]
Income Tax Expense (Benefit)	$ 41.7	$ 46.6	$ 37.9	$ 45.4
Gross unrecognized tax benefits	2.8		2.8
Total amount of unrecognized tax benefits, if recognized, would affect the effective tax rate	2.3		2.3
New Accounting Pronouncement, Early Adoption, Effect [Member] | Other Noncurrent Assets [Member]
Income Tax Contingency [Line Items]
Income Tax Expense (Benefit)	$ 3.1		$ 3.1