Suspended Wells-Exploratory Capitalized Well Costs (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		$ 1,025	$ 833	$ 557
2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		734
2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		142
2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		149
Greater Poseidon-Australia [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	177
Greater Poseidon-Australia [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	165
Greater Poseidon-Australia [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	12
Caldita/Barossa-Australia [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	77
Caldita/Barossa-Australia [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	77
FAN-Senegal [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	117
FAN-Senegal [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	117
FAN-Senegal [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
FAN-Senegal [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
Fiord West-Alaska [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	16
Fiord West-Alaska [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	0
Fiord West-Alaska [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	16
Greater Clair-UK [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	127
Greater Clair-UK [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	113
Greater Clair-UK [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	14
Greater Clair-UK [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
Kamunsu East-Malaysia
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	19
Kamunsu East-Malaysia | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	19
Limbayong-Malaysia
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	23
Limbayong-Malaysia | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	23
NC 98-Libya [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	15
NC 98-Libya [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	11
NC 98-Libya [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	0
NC 98-Libya [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	4
NPR-A-Alaska [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	93
NPR-A-Alaska [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	70
NPR-A-Alaska [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	17
NPR-A-Alaska [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	6
Shenandoah-Lower 48 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	94
Shenandoah-Lower 48 [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	51
Shenandoah-Lower 48 [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	43
Shenandoah-Lower 48 [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
SNE-Senegal [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	23
SNE-Senegal [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	23
SNE-Senegal [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
SNE-Senegal [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
Sunrise-Australia[Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	13
Sunrise-Australia[Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	0
Sunrise-Australia[Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	0
Sunrise-Australia[Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1]	13
Surmont 3 and beyond-Canada [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	89
Surmont 3 and beyond-Canada [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	58
Surmont 3 and beyond-Canada [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	14
Surmont 3 and beyond-Canada [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	17
Tiber-Lower 48 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	100
Tiber-Lower 48 [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	60
Tiber-Lower 48 [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[2]	40
Tiber-Lower 48 [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year		0
Other of $10 million or less each [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1],[2]	42
Other of $10 million or less each [Member] | 2012-2014 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1],[2]	24
Other of $10 million or less each [Member] | 2009-2011 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1],[2]	2
Other of $10 million or less each [Member] | 2002-2008 [Member]
Aging of exploratory well costs that have been capitalized for more than one year
Aging of Exploratory Well Cost that have been capitalized for more than one year	[1],[2]	$ 16

[1] Appraisal drilling complete; costs being incurred to assess development.

[2] Additional appraisal wells planned.