Segment Disclosures and Related Information - Assets (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Assets [Abstract]
Consolidated total assets	$ 120,025	$ 118,057
Alaska [Member]
Assets [Abstract]
Consolidated total assets	12,073	11,662
Lower 48 and Latin America [Member]
Assets [Abstract]
Consolidated total assets	30,295	29,571
Canada [Member]
Assets [Abstract]
Consolidated total assets	21,250	22,394
Europe [Member]
Assets [Abstract]
Consolidated total assets	17,570	17,299
Asia Pacific and Middle East [Member]
Assets [Abstract]
Consolidated total assets	26,094	25,473
Other International [Member]
Assets [Abstract]
Consolidated total assets	1,678	1,610
Corporate and Other [Member]
Assets [Abstract]
Consolidated total assets	9,446	8,367
Discontinued operations [Member]
Assets [Abstract]
Consolidated total assets	$ 1,619	$ 1,681