Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income tax provision	$ 69.9	$ 60.9	$ 178.3	$ 170.1
Effective income tax rate, percent	(35.40%)	(36.80%)	34.90%	36.60%
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			$ 163.7	$ 110.8