CONSOLIDATED BALANCE SHEET (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Federal funds sold and securities borrowed or purchased under agreements to resell, at fair value	$ 167,748	$ 160,589
Trading account assets, pledged to creditors	118,594	105,458
Investments, pledged to creditors	25,726	21,423
Investments, at fair value	287,339	294,463
Loans at fair value	4,988	5,287
Other assets, at fair value	13,669	13,299
Federal funds purchased and securities loaned or sold under agreements to repurchase, at fair value	124,854	116,689
Short-term borrowings, at fair value	915	818
Long-term debt, at fair value	28,151	29,764
Other liabilities, at fair value	2,721	2,910
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, authorized shares (in shares)	30,000,000	30,000,000
Preferred stock, issued shares, at aggregate liquidation value (in shares)	125,038	102,038
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	6,000,000,000	6,000,000,000
Common stock, issued shares (in shares)	3,062,087,203	3,043,153,204
Treasury stock, shares (in shares)	19,202,603	14,269,301
U.S.
Interest-bearing deposits, at fair value	889	889
Outside of U.S.
Interest-bearing deposits, at fair value	667	558
Consumer
Loans at fair value	1,202	1,231
Corporate
Loans at fair value	3,786	4,056
Consolidated VIEs
Long-term debt, at fair value	1,285	1,330
Consolidated VIEs | Consumer
Loans at fair value	1,159	1,191
Consolidated VIEs | Corporate
Loans at fair value	$ 147	$ 157