Asset Impairments (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	$ 500	$ 86	$ 104
Onshore US [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	42	39	39
Deepwater Gulf of Mexico [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	350	0	34
Israel [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	14	47	31
North Sea [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairments	$ 94	$ 0	$ 0