Loan Sale and Servicing Activities and Variable Interest Entities (Principal Balance, Delinquent Loans (Loans 90 Days or More Past Due), and Net Charge-Offs Related to Serviced Loans) (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	Dec. 31, 2013
Residential Mortgages [Member]
Total principal balance	$ 82,590		$ 82,590		$ 85,758
Delinquent loans	3,034		3,034		3,562
Net charge-offs	34	65	75	135
Commercial Mortgages [Member]
Total principal balance	63,130		63,130		62,872
Delinquent loans	1,434		1,434		2,353
Net charge-offs	345	101	700	344
Home Equity Loans Lines [Member]
Total principal balance	4,130		4,130		4,321
Delinquent loans	1,401		1,401		1,404
Net charge-offs	15	35	32	79
Prior period correction of an error					$ 581