Operating Segments and Geographic Data (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Segment Reporting Information [Line Items]
Segment Earnings	$ 5,665	[1]	$ 5,365	[1]	$ 10,177	[1]	$ 11,543	[1]
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment Earnings	5,985	[1]	5,715	[1]	11,002	[1]	12,332	[1]
Operating Segments [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	5,264	[1]	4,949	[1]	9,571	[1]	10,865	[1]
Operating Segments [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	721	[1]	766	[1]	1,431	[1]	1,467	[1]
Operating Segments [Member] | United States [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	1,054	[1]	1,083	[1]	1,966	[1]	2,215	[1]
Operating Segments [Member] | United States [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	517	[1]	138	[1]	939	[1]	273	[1]
Operating Segments [Member] | International [Member] | Upstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	4,210	[1]	3,866	[1]	7,605	[1]	8,650	[1]
Operating Segments [Member] | International [Member] | Downstream [Member]
Segment Reporting Information [Line Items]
Segment Earnings	204	[1]	628	[1]	492	[1]	1,194	[1]
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Interest Income	21	[1]	18	[1]	38	[1]	39	[1]
Other	$ (341)	[1]	$ (368)	[1]	$ (863)	[1]	$ (828)	[1]

[1] Effective January 1, 2014, International Upstream prospectively includes selected amounts previously recognized in International Downstream, which are not material to the company’s results of operations or financial position.