Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Consolidated Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (545)	$ 82	$ (310)	$ 561
Net change in unrealized gains (losses), net of tax as applicable on:
Securities available-for-sale, not other-than-temporarily impaired	248	290	121	142
Other-than-temporary impaired debt securities available for sale				1
Other-than-temporarily impaired debt securities held to maturity				11
Adjustment to reverse other-than-temporary impairment on securities held-to-maturity due to deconsolidation of a variable interest entity				142
Derivatives designated as cash flow hedges	(37)	(14)		(17)
Unrecognized actuarial gains, transition obligation and prior service costs relating to pension and postretirement benefits, net of tax		1	1	2
Other comprehensive income, net of tax	211	277	122	281
Comprehensive income (loss)	$ (334)	$ 359	$ (188)	$ 842