v2.4.0.6
Earnings Per Share (Earnings Per Share Computations) (Details) (USD $)
In Millions, except Per Share data, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Jun. 30, 2012
Jun. 30, 2011
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Earnings from continuing operations, Earnings $ 477 $ 184 $ 891 $ 573
Basic earnings per share, Earnings per Share $ 1.18 $ 0.44 $ 2.20 $ 1.35
Diluted earnings per share, Earnings per Share $ 1.18 $ 0.43 $ 2.20 $ 1.34
Antidilutive securities excluded from computation of earnings per share, amount 8.9 3.1 6.7 3.1
Earnings [Member]
       
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Earnings from continuing operations, Earnings 477 184 891 573
Attributable to participating securities, Earnings (6) (2) (10) (6)
Basic earnings per share, Earnings 471 182 881 567
Diluted earnings per share, Earnings $ 471 $ 182 $ 881 $ 567
Common Stock [Member]
       
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Earnings from continuing operations, Common Shares 404 422 404 425
Attributable to participating securities, Common Shares (4) (5) (4) (5)
Basic earnings per share, Common Shares 400 417 400 420
Dilutive effect of potential common shares issuable, Common Shares   2 1 2
Diluted earnings per share, Common Shares 400 419 401 422