Consolidated Statements of Comprehensive Income Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net Income (Loss) Attributable to Parent	$ 483	$ 399	$ 912	$ 804
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(201)	175	(115)	284
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(34)	(36)	10	(86)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	6	2	(67)	32
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(229)	141	(172)	230
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 254	$ 540	$ 740	$ 1,034