Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 569	$ 450	$ 1,378	$ 1,260
Postretirement and postemployment plans
Change in actuarial loss and other	34	(90)	180	(80)
Income tax (provision) benefit on postretirement and postemployment plans	(13)	32	(67)	28
Postretirement and postemployment plans, net of tax	21	(58)	113	(52)
Derivative hedges
Net unrecognized gain	0	1	0	1
Income tax provision on derivatives	0	0	0	0
Derivative hedges, net of tax	0	1	0	1
Foreign currency translation and other
Net unrecognized gain	1	0	(3)	0
Income tax benefit on foreign currency translation and other	0	0	1	0
Foreign currency translation and other, net of tax	1	0	(2)	0
Other comprehensive income (loss)	22	(57)	111	(51)
Comprehensive income	$ 591	$ 393	$ 1,489	$ 1,209