v2.4.0.6
Stockholders' Equity (Narrative) (Details) (USD $)
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Schedule of Capitalization, Equity [Line Items]      
Authorized capital stock, common stock shares 1,000,000,000 1,000,000,000  
Common stock par value per share $ 0.10 $ 0.1  
Authorized capital stock, preferred stock shares 4,500,000    
Preferred stock par value per share $ 1.00    
Redemption price multiplier 100    
Authorized repurchase of common shares under share repurchase program $ 3,500,000,000    
Repurchases of common stock 3,500,000,000    
Common shares repurchased 49,200,000    
Repurchase amount of common shares per share $ 71.18    
Payments of ordinary dividends 278,000,000 281,000,000 284,000,000
Common stock, cash paid on dividends, per share $ 0.67 $ 0.64 $ 0.64
Stock Repurchase Program 2010 [Member]
      
Schedule of Capitalization, Equity [Line Items]      
Repurchases of common stock $ 2,299,000,000 $ 1,201,000,000  
Common shares repurchased 30,900,000 18,300,000  
Repurchase amount of common shares per share $ 74.49 $ 65.58  
Series A Junior Participating Preferred Stock [Member]
      
Schedule of Capitalization, Equity [Line Items]      
Authorized capital stock, preferred stock shares 2,900,000    
Preferred stock issued 0    
Preferred stock outstanding 0    
Cumulative quarterly dividends per share, minimum $ 1.00    
Preferred stock cumulative quarterly dividends aggregate per share multiplier 100    
Preferred stock, number of votes per share held 100    
Maximum [Member]
      
Schedule of Capitalization, Equity [Line Items]      
Common stock, cash paid on dividends, per share $ 0.17    
Minimum [Member]
      
Schedule of Capitalization, Equity [Line Items]      
Common stock, cash paid on dividends, per share $ 0.16