Other Assets (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Other Assets [Abstract]
Accounts receivable	$ 5,529		$ 4,255
Corporate/bank owned life insurance	4,424		4,360
Income taxes receivable	2,399		3,099
Equity in joint ventures and other investments	3,021	[1]	2,664	[1]
Fails to deliver	2,076		1,148
Software	1,210		1,117
Fair value of hedging derivatives	1,187		989
Prepaid expenses	438		508
Prepaid pension assets	470		419
Due from customers on acceptances	211		376
Other	1,736		1,533
Total other assets	$ 22,701		$ 20,468

[1] Includes Federal Reserve Bank stock of $440 million and $436 million, respectively, at cost.