Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (599)	$ (192)	$ (5,695)	$ (769)
Postretirement and postemployment plans
Change in actuarial loss and other	5	0	17	(5)
Income tax provision	19	0	19	2
Postretirement and postemployment plans, net of tax	24	0	36	(3)
Derivative hedges
Net unrecognized gain (loss)	0	2	(13)	2
Reclassification of gains on terminated derivative hedges	(46)	0	(47)	0
Income tax provision	21	0	21	0
Derivative hedges, net of tax	(25)	2	(39)	2
Foreign currency hedges
Net recognized gain reclassified to discontinued operations	0	0	34	0
Income tax benefit (provision)	0	0	(4)	0
Foreign currency hedges, net of tax	0	0	30	0
Other, Net of Tax	1	1	2	(1)
Other comprehensive income (loss)	0	3	29	(2)
Comprehensive income (loss)	$ (599)	$ (189)	$ (5,666)	$ (771)