Quarterly report pursuant to Section 13 or 15(d)

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

v3.5.0.2
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 12 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2015
Stockholders Equity Note [Roll Forward]          
Common stock purchases     (19.5)    
Balance at beginning of period     $ 2,470    
Net income $ 1,270 $ 1,257 3,670 $ 3,513  
Common stock purchases     (2,029)    
Balance at end of period $ 2,743   $ 2,743   $ 2,470
Class A common stock          
Stockholders Equity Note [Roll Forward]          
Balance at beginning of period     194.0 201.0 201.0
Common stock purchases     (4.0) (3.0)  
Stock award plans     5.0 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     (12.0) (8.0)  
Stock Issued During Period, Value, Conversion of Convertible Securities     $ 0 $ 0  
Balance at end of period 185.0 196.0 185.0 196.0 194.0
Balance at beginning of period     $ 2 $ 2 $ 2
Common stock issuances     0 0  
Common stock purchases     0 0  
Balance at end of period $ 2 $ 2 $ 2 $ 2 $ 2
Class B common stock          
Stockholders Equity Note [Roll Forward]          
Balance at beginning of period     693.0 705.0 705.0
Common stock purchases     (16.0) (17.0)  
Conversions of Class A to Class B common stock     (12.0) (8.0)  
Stock Issued During Period, Value, Conversion of Convertible Securities     $ 0 $ 0  
Balance at end of period 689.0 696.0 689.0 696.0 693.0
Balance at beginning of period     $ 7 $ 7 $ 7
Common stock purchases     0 0  
Balance at end of period $ 7 $ 7 7 7 7
Additional Paid-in Capital          
Stockholders Equity Note [Roll Forward]          
Balance at beginning of period     0 0 0
Stock award plans     423 391  
Common stock issuances     233 245  
Option premiums received (paid)     155 (69)  
Common stock purchases     (811) (567)  
Balance at end of period 0 0 0 0 0
Retained Earnings          
Stockholders Equity Note [Roll Forward]          
Balance at beginning of period     6,001 5,726 5,726
Net income     3,670 3,513  
Dividends ($0.57 and $0.52 per share)     (2,093) (2,000)  
Common stock purchases     (1,193) (1,468)  
Balance at end of period $ 6,385 $ 5,771 $ 6,385 $ 5,771 $ 6,001
Common stock, cash paid for dividends, per share     $ 2.34 $ 2.19