CONSOLIDTED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	$ (55)	$ (135)	$ (3)
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax	25	18	(35)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	48	13	41
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax	(52)	(34)	(16)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax	(19)	(32)	1
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	3	(3)	0
Other comprehensive income (loss) related to equity method investee, tax	$ (7)	$ (8)