v2.4.0.8
Financial Instruments - Information on Available-for-sale Investments (Detail) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]    
Fair Value $ 11,868 $ 10,202
Amortized Cost 11,787 10,115
Gross Unrealized Gains 110 93
Gross Unrealized Losses (29) (6)
Commercial paper [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 1,206 2,150
Amortized Cost 1,206 2,150
Gross Unrealized Gains      
Gross Unrealized Losses      
Corporate notes and bonds [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 7,054 5,063
Amortized Cost 7,037 5,013
Gross Unrealized Gains 32 52
Gross Unrealized Losses (15) (2)
Asset-backed securities [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 1,300 837
Amortized Cost 1,303 835
Gross Unrealized Gains 1 3
Gross Unrealized Losses (4) (1)
U.S. government and agency securities [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 1,236 1,206
Amortized Cost 1,239 1,204
Gross Unrealized Gains 1 2
Gross Unrealized Losses (4)   
Mortgage-backed securities [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 476 435
Amortized Cost 479 436
Gross Unrealized Gains 2 2
Gross Unrealized Losses (5) (3)
Foreign government bonds [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 125 108
Amortized Cost 126 107
Gross Unrealized Gains 0 1
Gross Unrealized Losses (1)   
Equity securities [Member]
    
Schedule of Available-for-sale Securities [Line Items]    
Fair Value 471 403
Amortized Cost 397 370
Gross Unrealized Gains 74 33
Gross Unrealized Losses