Interest Income and Interest Expense (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Interest income
Loans	$ 8,513	$ 9,102
Securities	1,890	2,295
Trading assets	2,273	2,394
Federal funds sold and securities purchased under resale agreements	514	651
Securities borrowed	(6)	37
Deposits with banks	163	152
Other assets	80	70
Total interest income	13,427	14,701
Interest expense
Interest-bearing deposits	545	722
Short-term and other liabilities	520	409
Long-term debt	1,295	1,722
Beneficial interests issued by consolidated VIEs	134	182
Interest expense	2,494	3,035
Net interest income	10,933	11,666
Provision for credit losses	617	726
Net interest income after provision for credit losses	$ 10,316	$ 10,940