Operating Segments and Geographic Data (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Segment Earnings	$ 571	$ 5,665	$ 3,138	$ 10,177
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment Earnings	737	5,985	3,720	11,002
Operating Segments [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	(2,219)	5,264	(659)	9,571
Operating Segments [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	2,956	721	4,379	1,431
Operating Segments [Member] | United States [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	(1,038)	1,054	(1,498)	1,966
Operating Segments [Member] | United States [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	731	517	1,437	939
Operating Segments [Member] | International [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	(1,181)	4,210	839	7,605
Operating Segments [Member] | International [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	2,225	204	2,942	492
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Interest Income	16	21	32	38
Other	$ (182)	$ (341)	$ (614)	$ (863)