Quarterly report pursuant to Section 13 or 15(d)

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

v3.8.0.1
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
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period $ 994      
Net income attributable to common shareowners 1,345 $ 1,166    
Balance at end of period $ 1,344      
Common stock, cash paid for dividends, per share $ 0.91 $ 0.83    
Class A common stock        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period $ 2 $ 2    
Balance at beginning of period, shares 173 180    
Common stock purchases $ 0 $ 0    
Common stock purchases, shares (1) (1)    
Stock award plans $ 0 $ 0    
Stock award plans, shares 3 3    
Common stock issuances $ 0 $ 0    
Common stock issuances, shares 2 1    
Conversions of class A to class B common stock $ 0 $ 0    
Conversions of Class A to Class B common stock, shares (3) (3)    
Balance at end of period $ 2 $ 2    
Balance at end of period, shares 174 180    
Class B common stock        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period $ 7 $ 7    
Balance at beginning of period, shares 687 689    
Common stock purchases $ 0 $ 0    
Common stock purchases, shares (1) (3)    
Conversions of class A to class B common stock $ 0 $ 0    
Conversions of Class A to Class B common stock, shares (3) (3)    
Balance at end of period $ 7 $ 7    
Balance at end of period, shares 689 689    
Additional Paid-in Capital        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period $ 0 $ 0    
Common stock purchases (136) (174)    
Stock award plans 20 15    
Common stock issuances 155 132    
Option premiums received (paid) (39) 27    
Balance at end of period 0 0    
Retained Earnings        
Stockholders Equity Note [Roll Forward]        
Balance at beginning of period 5,852 4,880    
Common stock purchases (119) (275)    
Net income attributable to common shareowners 1,345 1,166    
Balance at end of period 6,973 4,997    
Dividends ($0.91 and $0.83 per share) $ (840) $ (774)    
Reclassification from AOCI pursuant to the early adoption of ASU 2018-02     $ 735 $ 0