Fair Value (Fair Value Option - Changes in Fair Value) (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
Prior period reclass between residential mortgage loans held for sale and residential mortgage portfolio loans		$ 13		$ 13
Customer Resale Agreements [Member]
Gains (Losses) - FVO: Changes in Fair Value		(3)	(1)	(5)
Trading Loans [Member]
Gains (Losses) - FVO: Changes in Fair Value	1	1	1	2
Loans Held For Sale [Member] | Commercial Mortgage [Member]
Gains (Losses) - FVO: Changes in Fair Value	5	(13)	7	(12)
Loans Held For Sale [Member] | Residential Mortgage [Member]
Gains (Losses) - FVO: Changes in Fair Value	64	(65)	129	(8)
Loans - Portfolio [Member] | Residential Mortgage [Member]
Gains (Losses) - FVO: Changes in Fair Value	59	26	87	32
BlackRock Series C Preferred Stock
Gains (Losses) - FVO: Changes in Fair Value	5		3	60
Other Borrowed Funds [Member]
Gains (Losses) - FVO: Changes in Fair Value	$ 7	$ (3)	$ 3	$ (3)