Financial Derivatives (Derivatives Not Designated as Hedging Instruments under GAAP) (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
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	$ 94		$ 419		$ 413		$ 604
Residential Mortgages [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	88	[1]	327	[1]	330	[1]	489	[1]
Residential Mortgages [Member] | Residential Mortgage Servicing Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	67		339		273		504
Residential Mortgages [Member] | Loan Sales Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	21		(12)		57		(15)
Commercial Mortgage Banking [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	(6)		(3)		14		(4)
Commercial Mortgage Banking [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	(4)	[2],[3]	(7)	[2],[3]	17	[2],[3]	(12)	[2],[3]
Commercial Mortgage Banking [Member] | Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	(2)	[2]	4	[2]	(3)	[2]	8	[2]
Customer Contracts [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	51	[2]	51	[2]	127	[2]	112	[2]
Customer Contracts [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	37		6		64		46
Customer Contracts [Member] | Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments			2		(2)		4
Customer Contracts [Member] | Equity Contract [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	1		1		(4)		(2)
Customer Contracts [Member] | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	13		42		69		64
Other Risk Management Activity [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	(39)	[2]	44	[2]	(58)	[2]	7	[2]
Other Risk Management Activity [Member] | Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	(5)		(40)		(12)		(42)
Other Risk Management Activity [Member] | Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments			1		(1)		(1)
Other Risk Management Activity [Member] | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments			3		(1)
Other Risk Management Activity [Member] | Other Derivative Contracts [Member]
Derivatives, Fair Value [Line Items]
Total gains (losses) from derivatives not designated as hedging instruments	$ (34)	[4]	$ 80	[4]	$ (44)	[4]	$ 50	[4]

[1] Included in Residential mortgage noninterest income.

[2] Included in Other noninterest income.

[3] Included in Corporate services noninterest income.

[4] Includes BlackRock LTIP, a forward purchase commitment for certain loans upon conversion from a variable rate to a fixed rate, and the swap entered into in connection with the sale of a portion of Visa Class B common shares.