Income Taxes (Components Of Deferred Income Taxes) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets
Retirement benefits	$ 287.8	$ 405.3
Accrued expenses	342.8	431.2
Insurance reserves	213.1	221.2
Net operating loss carryforwards	17.2	19.2
Bad debt reserves	124.8	108.2
State income tax	32.9	79.3
Deferred compensation	52.0	55.7
Investment basis difference	166.3	138.2
Other	84.0	47.0
Total deferred tax assets	1,320.9	1,505.3
Valuation allowance	(24.1)	(18.1)
Total deferred tax assets, net of valuation allowance	1,296.8	1,487.2
Deferred tax liabilities
Unrealized gains on securities	266.5	431.0
Trademarks and other non-amortizable intangible assets	2,200.5	2,200.5
Subscriber base, provider and hospital networks	370.9	447.7
Internally developed software and other amortization differences	703.9	599.3
Retirement benefits	231.5	214.1
Debt discount	186.9	189.7
State deferred tax	55.3	165.9
Depreciation and amortization	33.1	73.9
Other	190.4	151.6
Total deferred tax liabilities	4,239.0	4,473.7
Deferred tax asset-current	383.0	236.4
Deferred tax liability-noncurrent	(3,325.2)	(3,222.9)
Net deferred tax liability	$ (2,942.2)	$ (2,986.5)