Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income tax provision	$ 63.7	$ 69.9	$ 181.0	$ 178.3
Effective income tax rate, percent	34.80%	35.40%	34.80%	34.90%
Effective income tax rate, at federal statutory income tax rate, percent	35.00%	35.00%	35.00%	35.00%
Cash paid for taxes, net of refunds received			$ 158.8	$ 163.7