Consolidated Statements of Comprehensive Income Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net Income (Loss) Attributable to Parent	$ 537	$ 576	$ 1,449	$ 1,380
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	119	(37)	4	246
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	84	(82)	94	(168)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	3	1	(64)	34
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	206	(118)	34	112
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 743	$ 458	$ 1,483	$ 1,492