Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Less accumulated depreciation, depletion and amortization	$ (21,884)	$ (21,895)
Property, plant and equipment, net	29,040	28,145
North America Exploration and Production [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	16,717	14,973
International Exploration and Production [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	2,741	3,590
Oil Sands Mining Segment [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	9,455	9,447
Corporate [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	127	135
Libya [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 771
Proved Developed and Undeveloped Reserves, Net (BOE)	243,000,000