Quarterly report pursuant to Section 13 or 15(d)

Activity in Accumulated Other Comprehensive Income (Loss) (Phantoms) (Detail)

v3.19.1
Activity in Accumulated Other Comprehensive Income (Loss) (Phantoms) (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Balance at beginning of period $ (4,994)      
Change in foreign currency translation adjustment, net of tax 53 $ (6)    
Balance at end of period (4,818) (5,638)    
Foreign currency translation gain (loss):        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Balance at beginning of period (1,126) (930)    
Change in foreign currency translation adjustment, net of tax 53 (6)    
Balance at end of period (1,073) (983)    
Aggregate adjustment for the period, tax 9 (9)    
Unrealized gain (loss) on marketable securities, net of tax:        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Balance at beginning of period (2) (2)    
Balance at end of period 2 (5)    
Current period changes in fair value, tax effect 1 (1)    
Reclassification to earnings, tax effect 0 1    
Unrealized gain (loss) on cash flow hedges, net of tax:        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Balance at beginning of period 40 (366)    
Reclassification to retained earnings pursuant to the early adoption of ASU 2018-02     $ 0 $ (79)
Balance at end of period 116 (511)    
Current period changes in fair value, tax effect 28 (33)    
Reclassification to earnings, tax effect (13) 36    
Accumulated Defined Benefit Plans Adjustment [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Balance at beginning of period (3,906) (3,569)    
Balance at end of period (3,863) (4,139)    
Reclassification to earnings, tax effect 13 12    
Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement or Curtailment Gain (Loss), Tax $ 0 $ 0