Statement of Changes in Total Equity (USD $)
In Millions, unless otherwise specified
Total
Shareholders' Equity [Member]
Common Stock [Member]
Additional Paid In Capital [Member]
Accumulated Other Comprehensive Income [Member]
Retained Earnings [Member]
Treasury Stock [Member]
Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2013 $ 96              
Total Equity, beginning of period at Dec. 31, 2013 10,581 10,567 92 3,356 (520) 13,676 (6,037) 14
Increase (Decrease) In Stockholders Equity [Roll Forward]                
Effect of issuing stock for employee benefit plans 28 28   36   (57) 49  
Other comprehensive income (loss) 88 87     87     1
Net income 526 528       528   (2)
Common dividends declared (per share: $0.04) (11) (11)       (11)    
Repurchase of common stock (643) (643)         (643)  
Redeemable Noncontrolling Interest [Roll Forward]                
Other comprehensive income (loss) (3)              
Net income 3              
Ending Balance at Mar. 31, 2014 96              
Total Equity, end of period at Mar. 31, 2014 10,569 10,556 92 3,392 (433) 14,136 (6,631) 13
Beginning Balance at Dec. 31, 2014 90              
Total Equity, beginning of period at Dec. 31, 2014 10,789 10,774 74 2,769 (936) 10,289 (1,422) 15
Increase (Decrease) In Stockholders Equity [Roll Forward]                
Effect of issuing stock for employee benefit plans 62 62   55   (177) 184  
Other comprehensive income (loss) 2 2     2      
Net income 531 533       533   (2)
Common dividends declared (per share: $0.04) (10) (10)       (10)    
Repurchase of common stock (418) (418)         (418)  
Capital contribution by noncontrolling interest 2 (1)   (1)       3
Redeemable Noncontrolling Interest [Roll Forward]                
Other comprehensive income (loss) (9)              
Capital contribution by noncontrolling interest 2              
Ending Balance at Mar. 31, 2015 83              
Total Equity, end of period at Mar. 31, 2015 $ 10,958 $ 10,942 $ 74 $ 2,823 $ (934) $ 10,635 $ (1,656) $ 16