Operating Segments and Geographic Data (Details 1) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Segment Assets
Segment Assets	$ 265,431	[1]	$ 253,753	[1]
Goodwill	4,621	[1]	4,639	[1]
United States [Member]
Segment Assets
Segment Assets	78,135	[1]	76,591	[1]
International [Member]
Segment Assets
Segment Assets	182,675	[1]	172,523	[1]
Operating Segments [Member]
Segment Assets
Segment Assets	245,634	[1]	231,268	[1]
Operating Segments [Member] | Upstream [Member]
Segment Assets
Segment Assets	201,111	[1]	187,171	[1]
Goodwill	4,621	[1]	4,639	[1]
Operating Segments [Member] | Upstream [Member] | United States [Member]
Segment Assets
Segment Assets	47,703	[1]	45,436	[1]
Operating Segments [Member] | Upstream [Member] | International [Member]
Segment Assets
Segment Assets	148,787	[1]	137,096	[1]
Operating Segments [Member] | Downstream [Member]
Segment Assets
Segment Assets	44,523	[1]	44,097	[1]
Operating Segments [Member] | Downstream [Member] | United States [Member]
Segment Assets
Segment Assets	23,650	[1]	23,829	[1]
Operating Segments [Member] | Downstream [Member] | International [Member]
Segment Assets
Segment Assets	20,873	[1]	20,268	[1]
Corporate, Non-Segment [Member] | United States [Member]
Segment Assets
Segment Assets	6,782	[1]	7,326	[1]
Corporate, Non-Segment [Member] | International [Member]
Segment Assets
Segment Assets	13,015	[1]	15,159	[1]
Corporate, Non-Segment [Member] | All Other [Member]
Segment Assets
Segment Assets	$ 19,797	[1]	$ 22,485	[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.