Consolidated Statements of Income (USD $)
In Millions, except Per Share data, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Revenues    
Premiums $ 7,402 $ 6,676
Fees and other revenues 1,138 1,006
Net investment income 276 277
Mail order pharmacy revenues 578 495
Realized investment gains (losses):    
Total realized investment gains 73 42
Total revenues 9,467 8,496
Benefits and Expenses    
Global Health Care medical costs 4,604 4,031
Other benefit expenses 1,269 1,166
Mail order pharmacy cost of goods sold 492 414
Other operating expenses 2,204 1,980
Amortization of other acquired intangible assets 44 52
Total benefits and expenses 8,613 7,643
Income before Income Taxes 854 853
Income taxes:    
Current 308 310
Deferred 15 14
Total taxes 323 324
Net Income 531 529
Less: Net Income Attributable to Noncontrolling Interests (2) 1
Shareholders' Net Income $ 533 $ 528
Shareholders' Net Income Per Share:    
Basic $ 2.08 $ 1.96
Diluted $ 2.04 $ 1.92
Dividends Declared Per Share $ 0.04 $ 0.04