Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	$ 438.7	$ 410.2
Effective tax rate	38.80%	32.00%
Health Insurance Provider fee, nondeductible expense	$ 80.5