Discontinued Operations - Textuals (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Discontinued Operations [Abstract]
Deposit	$ 550
Kashagan [Member]
Other Discontinued Operations [Abstract]
Ownership percentage in equity investment	8.40%
Proceeds from asset dispositions		$ 5,392
Gain on sale, before tax		22
Carrying value at disposal		5,370
Other current assets at disposal		212
Long-term receivables at disposal		239
Amount of PP&E in carrying value of asset		5,149
Other current liabilities at disposal		144
Asset retirement obligation at disposal		86
Algeria [Member]
Other Discontinued Operations [Abstract]
Deposit		0
Proceeds from asset dispositions		1,652
Gain on sale, before tax		938
Carrying value at disposal		714
Other current assets at disposal		48
Amount of PP&E in carrying value of asset		883
Other current liabilities at disposal		41
Amount of deferred taxes in carrying value of asset		139
Asset retirement obligation at disposal		37
Nigeria Upstream Affiliates [Member]
Other Discontinued Operations [Abstract]
Deposit	$ 100	$ 15	$ 435
Deferred income taxes	825
Proceeds from asset dispositions	1,359
Gain on sale, before tax	1,052
Carrying value at disposal	307
Other current assets at disposal	233
Amount of PP&E in carrying value of asset	1,211
Other current liabilities at disposal	298
Asset retirement obligation at disposal	$ 14