Asset Impairments (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
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	$ 34	$ 0	$ 131	$ 0
US Properties, Primarily Shelf and Deepwater Gulf of Mexico [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	18	0	23	0
Mari-B (Offshore Israel)
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	14	0	14	0
McCulloch and Other North Sea Properties [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	$ 2	$ 0	$ 94	$ 0