Investments in Securities Accumulated Other Comprehensive Income 2 (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Investments, Debt and Equity Securities [Abstract]
Net income (loss)	$ 1,813	$ (5,085)	$ 9,650	$ (14,448)
Other comprehensive income (loss), net of tax effect:
Changes in net unrealized (losses) gains on available-for-sale securities (net of tax of $386 and $210, respectively, for the three months ended and net of tax of $536 and $142, respectively, for the nine months ended)	719	(391)	974	(264)
Reclassification adjustment for other-than-temporary impairments recognized in net income (loss) (net of tax of $13 and $92, respectively, for the three months ended and $245 and $120, respectively, for the nine months ended)	25	170	456	242
Reclassification adjustment for gains included in net income (loss) (net of tax of $2 and $10, respectively for the three months ended and net of tax of $8 and $1, respectively, for the nine months ended)	(3)	23	(14)	2
Other	5	1	20	6
Other comprehensive income (loss)	746	(197)	1,436	(14)
Total comprehensive income (loss)	2,559	(5,282)	11,086	(14,462)
Other Comprehensive Income (Loss), Tax [Abstract]
Changes in net unrealized (losses) gains on available-for-sale securities, tax benefit (expense)	(386)	210	(536)	142
Reclassification adjustment for other-than-temporary impairments recognized in net income (loss), tax benefit (expense)	(13)	(92)	(245)	(120)
Reclassification adjustment for gains included in net income (loss), tax benefit (expense)	$ 2	$ (10)	$ 8	$ (1)