Industry Segments (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2013	Jun. 30, 2013 segment	Jun. 30, 2012 segment	Jun. 30, 2013 segment	Jun. 30, 2012 segment
Industry Segments
Number of reportable segments		3	3	3	3
Segment Information
Net sales		$ 5,962	$ 5,768	$ 11,834	$ 12,036
Pretax operating profit (loss)		2,228	2,207	4,431	4,906
Income taxes		(901)	(875)	(1,745)	(2,014)
Discontinued operations, net		(5)	(4)	(9)	(5)
Net income (loss)		1,322	1,328	2,677	2,887
Gain on sale of equity investment		131		131
Charge for former executives and consultants	55
Brazilian chemical facility
Segment Information
Gain on sale of equity investment	131
Oil and Gas
Segment Information
Net sales		4,721	4,495	9,161	9,397
Pretax operating profit (loss)		2,100	2,043	4,020	4,547
Net income (loss)		2,100	2,043	4,020	4,547
Chemical
Segment Information
Net sales		1,187	1,172	2,362	2,320
Pretax operating profit (loss)		275	194	434	378
Net income (loss)		275	194	434	378
Chemical | Brazilian chemical facility
Segment Information
Gain on sale of equity investment		131		131
Midstream and Marketing
Segment Information
Net sales		269	262	722	655
Pretax operating profit (loss)		48	77	263	208
Net income (loss)		48	77	263	208
Corporate and Eliminations
Segment Information
Net sales		(215)	(161)	(411)	(336)
Pretax operating profit (loss)		(195)	(107)	(286)	(227)
Income taxes		(901)	(875)	(1,745)	(2,014)
Discontinued operations, net		(5)	(4)	(9)	(5)
Net income (loss)		(1,101)	(986)	(2,040)	(2,246)
Charge for former executives and consultants		$ 55		$ 55