Operating Segments and Geographic Data (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Sales and Other Operating Revenues
Sales and other operating revenues	$ 55,660	[1]	$ 61,261	[1]	$ 174,336	[1]	$ 186,344	[1]
Upstream [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	6,009		7,644		19,353		22,262
Upstream [Member] | United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	5,579		6,891		17,512		20,914
Upstream [Member] | International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	12,801		13,758		40,501		41,165
Upstream [Member] | Subtotal [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	18,380		20,649		58,013		62,079
Upstream [Member] | Intersegment Elimination - United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(3,985)		(4,397)		(13,026)		(13,559)
Upstream [Member] | Intersegment Elimination - International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(8,386)		(8,608)		(25,634)		(26,258)
Downstream [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	49,560		53,493		154,691		163,682
Downstream [Member] | United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	21,558		23,128		66,899		69,174
Downstream [Member] | International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	28,042		30,407		87,890		94,644
Downstream [Member] | Subtotal [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	49,600		53,535		154,789		163,818
Downstream [Member] | Intersegment Elimination - United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(12)		(20)		(37)		(63)
Downstream [Member] | Intersegment Elimination - International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(28)		(22)		(61)		(73)
All Other Segments [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	91		124		292		400
All Other Segments [Member] | United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	424		401		1,186		1,163
All Other Segments [Member] | International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	11		12		36		34
All Other Segments [Member] | Subtotal [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	435		413		1,222		1,197
All Other Segments [Member] | Intersegment Elimination - United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(333)		(278)		(896)		(766)
All Other Segments [Member] | Intersegment Elimination - International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(11)		(11)		(34)		(31)
Sales and Other Operating Revenue [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	55,660		61,261		174,336		186,344
Sales and Other Operating Revenue [Member] | United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	27,561		30,420		85,597		91,251
Sales and Other Operating Revenue [Member] | International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	40,854		44,177		128,427		135,843
Sales and Other Operating Revenue [Member] | Subtotal [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	68,415		74,597		214,024		227,094
Sales and Other Operating Revenue [Member] | Intersegment Elimination - United States [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	(4,330)		(4,695)		(13,959)		(14,388)
Sales and Other Operating Revenue [Member] | Intersegment Elimination - International [Member]
Sales and Other Operating Revenues
Sales and other operating revenues	$ (8,425)		$ (8,641)		$ (25,729)		$ (26,362)

[1] * Includes excise, value-added and similar taxes:2,163 1,974 5,879 6,372