Fixed Assets - Property, Plant and Equipment (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 36,964	$ 35,164
Less accumulated depreciation	21,568	20,068
Fixed assets less accumulated depreciation	15,396	15,096	14,780
Land
Property Plant And Equipment [Line Items]
Property, plant and equipment	445	394
Building and Building Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment	3,733	3,534
Machinery and Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment	31,937	29,332
Seismic Vessels
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 849	$ 1,904