v3.10.0.1
Segment, Geographic and Other Revenue Information - Revenues By Geographic Area (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues [1] $ 53,647 $ 52,546 $ 52,824
United States [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues 25,329 26,026 26,369
Developed Europe [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues [2] 9,116 8,508 9,306
Developed Rest Of World [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues [3] 6,551 6,612 6,729
Emerging Markets [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues [4] $ 12,651 $ 11,399 $ 10,420
[1] Amounts may not add due to rounding.
[2] Developed Europe region includes the following markets: Western Europe, Scandinavian countries and Finland. Revenues denominated in euros were $7.3 billion in 2018, $6.8 billion in 2017 and $7.2 billion in 2016.
[3] Developed Rest of World region includes the following markets: Japan, Canada, South Korea, Australia and New Zealand.
[4] Emerging Markets region includes, but is not limited to, the following markets: Asia (excluding Japan and South Korea), Latin America, Eastern Europe, Africa, the Middle East, Central Europe and Turkey.