Cash Instruments (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	$ 638,513,000,000	$ 651,312,000,000
Total financial liabilities at fair value	377,677,000,000	388,669,000,000
Fair Value, Assets Measured on Recurring Basis, Gain (Loss) Included in Market Making Revenue	617,000,000	(202,000,000)
Fair Value, Assets Measured on Recurring Basis, Gain (Loss) Included in Other Principal Transactions Revenue	2,130,000,000	623,000,000
Fair Value, Assets Measured on Recurring Basis, Gain (Loss) Included in Interest Income	962,000,000	1,290,000,000
Fair Value, Investments Entities That Calculate Net Asset Value Per Share, Investment Redemption Amount In Certain Hedge Funds	1,060,000,000
Cash Instruments [Member]
Cash Instruments (Textuals) [Abstract]
Net Unrealized Gains / (Losses) Relating to Instruments Still Held at the Reporting Date	2,070,000,000	(310,000,000)
Level 2 [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	502,293,000,000	587,416,000,000
Total financial liabilities at fair value	318,764,000,000	319,160,000,000
Level 2 [Member] | CDOs backed by real estate assets [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	489,000,000	213,000,000
Level 2 [Member] | CDOs and CLOs backed by corporate and other debt obligations assets [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	284,000,000	403,000,000
Level 2 [Member] | Cash Instruments [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	135,374,000,000	134,033,000,000
Total financial liabilities at fair value	9,645,000,000	10,307,000,000
Level 3 [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	47,095,000,000	47,937,000,000
Total financial liabilities at fair value	25,679,000,000	25,498,000,000
Level 3 [Member] | CDOs backed by real estate assets [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	446,000,000	595,000,000
Level 3 [Member] | CDOs and CLOs backed by corporate and other debt obligations assets [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	1,760,000,000	1,190,000,000
Level 3 [Member] | Private equity investments [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	12,670,000,000	12,070,000,000
Level 3 [Member] | Real Estate Investments [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	1,580,000,000	1,100,000,000
Level 3 [Member] | Convertible Debt Securities [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	600,000,000	497,000,000
Level 3 [Member] | CDOs and CLOs backed by corporate obligations liabilities [Member]
Cash Instruments (Textuals) [Abstract]
Total financial liabilities at fair value		27,000,000
Level 3 [Member] | Cash Instruments [Member]
Cash Instruments (Textuals) [Abstract]
Total financial assets at fair value	35,749,000,000	34,685,000,000
Total financial liabilities at fair value	$ 642,000,000	$ 905,000,000