Income Taxes (Narrative) (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]
Provision for Income Taxes	$ 116.1	$ 118.6	$ 361.6	$ 380.1
Effective tax rate	31.10%	33.60%	32.10%	34.10%