Securities (Schedule of Credit Losses on Other-than-Temporarily Impaired Non-agency RMBS where Portion of the Unrealized Loss was Recognized in OCI (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Securities
Balance at beginning of period	$ 76	$ 93	$ 78	$ 98
Credit losses on securities without previous OTTI	0	0	1	0
Reductions for securities sold/settled during the period	(3)	(7)	(6)	(12)
Credit recoveries through yield	(1)	0	(1)	0
Balance at end of period	$ 72	$ 86	$ 72	$ 86