Other Financial Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	$ (44)		$ (33)		$ 58
Incurred
Debt	1,063		1,087		1,170
Other	73		192		154
Interest Costs Incurred, Total	1,136		1,279		1,324
Capitalized	(488)		(667)		(615)
Expensed	648		612		709
Other Income
Interest income	83		113		163
Other, net	283		261		306
Other Nonoperating Income	366		374		469
Research and Development Expenditures - expensed	263		258		221
Shipping and Handling Costs	1,360	[1]	1,137	[1]	1,338	[1]
Lower 48 [Member]
Other Income
Interest income	35		43		47
Canada [Member]
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	(4)		(6)		5
Europe [Member]
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	(55)		(31)		21
Other Income
Interest income	2		1
Asia Pacific and Middle East [Member]
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	0		(29)		29
Other Income
Interest income	6		8		11
Other International [Member]
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	(1)		2		1
Other Income
Interest income	0		1		9
Corporate and Other [Member]
Foreign Currency Transaction [Abstract]
Foreign currency transaction gain loss after tax	16		31		2
Other Income
Interest income	$ 40		$ 60		$ 96

[1] *Amounts included in production and operating expenses.