Segment Information - Fixed Assets Less Accumulated Depreciation by Geographic Area (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Fixed Assets less accumulated depreciation	$ 11,679	$ 11,576
Operating Segments | North America
Segment Reporting Information [Line Items]
Fixed Assets	5,715	5,121
Operating Segments | Latin America
Segment Reporting Information [Line Items]
Fixed Assets	898	1,042
Operating Segments | Europe
Segment Reporting Information [Line Items]
Fixed Assets	2,364	2,545
Operating Segments | Middle East & Asia
Segment Reporting Information [Line Items]
Fixed Assets	2,604	2,762
Unallocated
Segment Reporting Information [Line Items]
Fixed Assets	$ 98	$ 106