Segment Disclosures and Related Information - Assets (Details 2) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Assets [Abstract]
Consolidated total assets	$ 118,986	$ 118,057
Alaska [Member]
Assets [Abstract]
Consolidated total assets	12,667	11,662
Lower 48 [Member]
Assets [Abstract]
Consolidated total assets	30,749	29,552
Canada [Member]
Assets [Abstract]
Consolidated total assets	21,963	22,394
Europe [Member]
Assets [Abstract]
Consolidated total assets	16,968	17,223
Asia Pacific and Middle East [Member]
Assets [Abstract]
Consolidated total assets	26,276	25,473
Other International [Member]
Assets [Abstract]
Consolidated total assets	2,190	1,705
Corporate and Other [Member]
Assets [Abstract]
Consolidated total assets	8,062	8,367
Discontinued operations [Member]
Assets [Abstract]
Consolidated total assets	$ 111	$ 1,681