Quarterly report pursuant to Section 13 or 15(d)

Roll-forward of Common Stock, Additional Paid-in Capital, and Retained Earnings Accounts (Detail)

v3.3.0.814
Roll-forward of Common Stock, Additional Paid-in Capital, and Retained Earnings Accounts (Detail) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Stockholders Equity Note [Roll Forward]        
Common stock purchases     (20.2) (20.6)
Balance at beginning of period     $ 2,141  
Net income $ 1,257 $ 1,214 3,513 $ 2,579
Common stock purchases     (2,035) $ (2,042)
Balance at end of period $ 1,929   $ 1,929  
Class A common stock        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period     201.0 212.0
Common stock purchases     (3.0) (4.0)
Stock award plans     4.0 4.0
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures     $ 0 $ 0
Common stock issuances     2.0 2.0
Conversions of Class A to Class B common stock     (8.0) (11.0)
Stock Issued During Period, Value, Conversion of Convertible Securities     $ 0 $ 0
Balance at end of period 196.0 203.0 196.0 203.0
Balance at beginning of period     $ 2 $ 2
Common stock issuances     0 0
Common stock purchases     0 0
Balance at end of period $ 2 $ 2 $ 2 $ 2
Class B common stock        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period     705.0 712.0
Common stock purchases     (17.0) (17.0)
Conversions of Class A to Class B common stock     (8.0) (11.0)
Stock Issued During Period, Value, Conversion of Convertible Securities     $ 0 $ 0
Balance at end of period 696.0 706.0 696.0 706.0
Balance at beginning of period     $ 7 $ 7
Common stock purchases     0 0
Balance at end of period $ 7 $ 7 7 7
Additional Paid-in Capital        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period     0 0
Stock award plans     391 359
Common stock issuances     245 218
Option premiums received (paid)     (69) 53
Common stock purchases     (567) (630)
Balance at end of period 0 0 0 0
Retained Earnings        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period     5,726 6,925
Net income     3,513 2,579
Dividends ($0.57 and $0.52 per share)     (2,000) (1,863)
Common stock purchases     (1,468) (1,412)
Balance at end of period $ 5,771 $ 6,229 $ 5,771 $ 6,229
Common stock, cash paid for dividends, per share     $ 2.19 $ 2.01
Options Held [Member]        
Stockholders Equity Note [Roll Forward]        
Option premiums received (paid)     $ (69) $ 53