Income Taxes (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Income Taxes [Abstract]
Effective tax rate	32.80%	32.60%
Income tax benefit, merger expenses	$ 11.0
Effective tax rate, excluding merger expenses		33.50%
Unrecognized tax benefits	60.9
Unrecognized tax benefits that would impact effective tax rate	$ 50.8