v3.3.1.900
Equity (Changes in Common Stock) (Details) - shares
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Repurchases and retirements of common stock 116,000,000 81,000,000 49,000,000
Class A Common Stock [Member]      
Common Stock, Shares, Outstanding, Beginning Balance 2,131,137,862 2,138,000,000 2,122,000,000
Stock compensation plans 12,000,000 13,000,000 14,000,000
Repurchases and retirements of common stock (62,000,000) (22,000,000) 0
Employee stock purchase plan 2,000,000 2,000,000 2,000,000
Share Reclassification of Class A Special common stock 346,000,000    
Other 4,000,000    
Common Stock, Shares, Outstanding, Ending Balance 2,432,953,988 2,131,137,862 2,138,000,000
Class A Special Common Stock [Member]      
Common Stock, Shares, Outstanding, Beginning Balance 400,484,837 459,000,000 508,000,000
Stock compensation plans 0 0 0
Repurchases and retirements of common stock (54,000,000) (59,000,000) (49,000,000)
Employee stock purchase plan 0 0 0
Share Reclassification of Class A Special common stock (346,000,000)    
Other 0    
Common Stock, Shares, Outstanding, Ending Balance   400,484,837 459,000,000
Class B Common Stock [Member]      
Common Stock, Shares, Outstanding, Beginning Balance 9,444,375 9,000,000 9,000,000
Stock compensation plans 0 0 0
Repurchases and retirements of common stock 0 0 0
Employee stock purchase plan 0 0 0
Other 0    
Common Stock, Shares, Outstanding, Ending Balance 9,444,375 9,444,375 9,000,000