Consolidated Statements of Equity and Redeemable Equity (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements of Equity and Redeemable Equity
Gains (losses) on cash flow hedges, income tax effect	$ (29)	$ 25	$ 19
Amount of (gains) losses on cash flow hedges reclassified to earnings, income tax effect	(19)	15	61
Actuarial gain (loss) on postretirement obligations, settlements and plan amendments, income tax	32	(27)	(4)
(Gains) losses related to postretirement obligations reclassified to earnings, income tax	$ (3)	$ (2)	$ 5