Consolidated Statements of Financial Condition (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements of Financial Condition [Abstract]
Securities segregated for regulatory and other purposes	$ 30,484	$ 42,014
Securities purchased under agreements to resell and federal funds sold at fair value	141,331	187,789
Securities borrowed at fair value	38,395	47,621
Receivables from customers and counterparties at fair value	7,866	9,682
Financial instruments owned, at fair value pledged as collateral	67,177	53,989
Other assets at fair value	13,426	0
Deposits at fair value	5,100	4,526
Securities loaned at fair value	1,558	107
Other secured financings at fair value	30,337	30,019
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings, at fair value	17,595	17,854
Unsecured long-term borrowings at fair value	12,593	17,162
Other liabilities and accrued expenses at fair value	12,043	9,486
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, liquidation preference	$ 6,200	$ 3,100
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	4,000,000,000	4,000,000,000
Common stock, shares issued	816,807,400	795,555,310
Common stock, shares outstanding	465,148,387	485,467,565
Nonvoting common stock, par value	$ 0.01	$ 0.01
Nonvoting common stock, shares authorized	200,000,000	200,000,000
Treasury stock, par value	$ 0.01	$ 0.01
Treasury stock, shares	351,659,015	310,087,747