Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Statement of Income and Comprehensive Income [Abstract]
Net income	$ 450	$ 405	$ 1,260	$ 2,397
Postretirement and postemployment plans
Change in actuarial loss and other	(90)	13	(80)	110
Spin-off downstream business	0	0	0	968
Income tax benefit (provision) on postretirement and postemployment plans	32	6	28	(409)
Postretirement and postemployment plans, net of tax	(58)	19	(52)	669
Derivative hedges
Net unrecognized gain (loss)	1	(1)	1	9
Spin-off downstream business	0	0	0	(7)
Income tax provision on derivatives	0	0	0	(1)
Derivative hedges, net of tax	1	(1)	1	1
Foreign currency translation and other
Unrealized loss	0	0	0	(1)
Income tax provision on foreign currency translation and other	0	0	0	0
Foreign currency translation and other, net of tax	0	0	0	(1)
Other comprehensive income (loss)	(57)	18	(51)	669
Comprehensive income	$ 393	$ 423	$ 1,209	$ 3,066