Variable Interest Entities (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	$ 135,830,000,000	$ 131,362,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	10,134,000,000	10,558,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	118,000,000	148,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	21,675,000,000	21,820,000,000
Assets of Consolidated VIEs
Cash and cash equivalents	45,433,000,000	39,788,000,000
Cash and securities segregated for regulatory and other purposes	61,491,000,000	53,731,000,000
Receivables from brokers, dealers and clearing organizations	16,785,000,000	10,437,000,000
Receivables from customers and counterparties	77,367,000,000	67,703,000,000
Financial Instruments owned, at fair value	370,605,000,000	356,953,000,000
Other assets	27,472,000,000	28,059,000,000
Liabilities of Consolidated VIEs
Other secured financings	34,520,000,000	38,377,000,000
Payables to customers and counterparties	203,382,000,000	187,270,000,000
Financial Instruments Sold, Not yet Purchased, at Fair Value	149,639,000,000	140,717,000,000
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	56,554,000,000	47,842,000,000
Unsecured long-term borrowings	175,210,000,000	174,399,000,000
Other liabilities and accrued expenses	29,909,000,000	30,011,000,000
Non-Consolidated Variable Interest Entities (Textual) [Abstract]
Guarantees and derivative transactions with VIEs to which the firm transferred assets	4,100,000,000	4,520,000,000
Collateralized Mortgage Backed Securities [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	94,287,000,000	88,755,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	6,835,000,000	8,076,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	0	0
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	9,293,000,000	10,958,000,000
Collateralized Mortgage Backed Securities [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	5,605,000,000	6,887,000,000
Collateralized Mortgage Backed Securities [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	905,000,000	839,000,000
Collateralized Mortgage Backed Securities [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Collateralized Mortgage Backed Securities [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	2,673,000,000	3,128,000,000
Collateralized Mortgage Backed Securities [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	110,000,000	104,000,000
Corporate CDOs and CLOs [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	25,377,000,000	21,644,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	1,383,000,000	909,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	87,000,000	114,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	8,952,000,000	7,997,000,000
Corporate CDOs and CLOs [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	43,000,000	50,000,000
Corporate CDOs and CLOs [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	701,000,000	353,000,000
Corporate CDOs and CLOs [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,000,000	1,000,000
Corporate CDOs and CLOs [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	8,207,000,000	7,593,000,000
Corporate CDOs and CLOs [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Real estate, credit-related and other investing [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	8,813,000,000	12,568,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	1,421,000,000	1,063,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	1,000,000	1,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,745,000,000	1,188,000,000
Assets of Consolidated VIEs
Cash and cash equivalents	446,000,000	248,000,000
Cash and securities segregated for regulatory and other purposes	169,000,000	205,000,000
Receivables from brokers, dealers and clearing organizations	3,000,000	4,000,000
Receivables from customers and counterparties	0	1,000,000
Financial Instruments owned, at fair value	2,277,000,000	2,531,000,000
Other assets	2,546,000,000	3,369,000,000
Total	5,441,000,000	6,358,000,000
Liabilities of Consolidated VIEs
Other secured financings	2,037,000,000	2,434,000,000
Payables to customers and counterparties	0	0
Financial Instruments Sold, Not yet Purchased, at Fair Value	0	0
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	4,000,000	302,000,000
Unsecured long-term borrowings	173,000,000	6,000,000
Other liabilities and accrued expenses	1,691,000,000	2,004,000,000
Total	3,905,000,000	4,746,000,000
Real estate, credit-related and other investing [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Real estate, credit-related and other investing [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Real estate, credit-related and other investing [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	324,000,000	125,000,000
Real estate, credit-related and other investing [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Real estate, credit-related and other investing [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,421,000,000	1,063,000,000
Other asset-backed [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	4,267,000,000	5,513,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	220,000,000	266,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	25,000,000	19,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,360,000,000	1,364,000,000
Other asset-backed [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	18,000,000	12,000,000
Other asset-backed [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	190,000,000	247,000,000
Other asset-backed [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Other asset-backed [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,152,000,000	1,105,000,000
Other asset-backed [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Power-related [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	529,000,000	552,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	271,000,000	239,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	5,000,000	14,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	321,000,000	308,000,000
Power-related [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Power-related [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Power-related [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	50,000,000	69,000,000
Power-related [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Power-related [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	271,000,000	239,000,000
Investment funds [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	2,557,000,000	2,330,000,000
Carrying Value of the Firm's Variable Interests
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Assets	4,000,000	5,000,000
Carrying Value of the Firm's Variable Interests in Nonconsolidated VIEs - Liabilities	0	0
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	4,000,000	5,000,000
Investment funds [Member] | Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Investment funds [Member] | Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Investment funds [Member] | Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Investment funds [Member] | Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	0	0
Investment funds [Member] | Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	4,000,000	5,000,000
Principal-protected notes [Member]
Assets of Consolidated VIEs
Cash and cash equivalents	13,000,000	52,000,000
Cash and securities segregated for regulatory and other purposes	0	0
Receivables from brokers, dealers and clearing organizations	0	0
Receivables from customers and counterparties	0	0
Financial Instruments owned, at fair value	699,000,000	648,000,000
Other assets	0	0
Total	712,000,000	700,000,000
Liabilities of Consolidated VIEs
Other secured financings	3,234,000,000	3,224,000,000
Payables to customers and counterparties	36,000,000	0
Financial Instruments Sold, Not yet Purchased, at Fair Value	0	0
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	2,132,000,000	2,359,000,000
Unsecured long-term borrowings	0	0
Other liabilities and accrued expenses	305,000,000	0
Total	5,707,000,000	5,583,000,000
Municipal bond securitizations [Member]
Assets of Consolidated VIEs
Cash and cash equivalents	0	0
Cash and securities segregated for regulatory and other purposes	0	0
Receivables from brokers, dealers and clearing organizations	0	0
Receivables from customers and counterparties	0	0
Financial Instruments owned, at fair value	191,000,000	547,000,000
Other assets	0	0
Total	191,000,000	547,000,000
Liabilities of Consolidated VIEs
Other secured financings	200,000,000	630,000,000
Payables to customers and counterparties	0	0
Financial Instruments Sold, Not yet Purchased, at Fair Value	0	0
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	0	0
Unsecured long-term borrowings	0	0
Other liabilities and accrued expenses	0	0
Total	200,000,000	630,000,000
CDOs, mortgage-backed and other asset-backed [Member]
Assets of Consolidated VIEs
Cash and cash equivalents	48,000,000	39,000,000
Cash and securities segregated for regulatory and other purposes	0	0
Receivables from brokers, dealers and clearing organizations	0	0
Receivables from customers and counterparties	17,000,000	27,000,000
Financial Instruments owned, at fair value	580,000,000	550,000,000
Other assets	468,000,000	499,000,000
Total	1,113,000,000	1,115,000,000
Liabilities of Consolidated VIEs
Other secured financings	473,000,000	417,000,000
Payables to customers and counterparties	24,000,000	12,000,000
Financial Instruments Sold, Not yet Purchased, at Fair Value	58,000,000	55,000,000
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	0	0
Unsecured long-term borrowings	0	0
Other liabilities and accrued expenses	32,000,000	32,000,000
Total	587,000,000	516,000,000
CDOs backed by mortgage obligations [Member]
Non-consolidated Variable Interest Entities [Abstract]
Assets in VIE	5,550,000,000	6,140,000,000
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	2,780,000,000	3,250,000,000
Consolidated Variable Interest Entity, Total Carrying Amount [Member]
Assets of Consolidated VIEs
Cash and cash equivalents	507,000,000	339,000,000
Cash and securities segregated for regulatory and other purposes	169,000,000	205,000,000
Receivables from brokers, dealers and clearing organizations	3,000,000	4,000,000
Receivables from customers and counterparties	17,000,000	28,000,000
Financial Instruments owned, at fair value	3,747,000,000	4,276,000,000
Other assets	3,014,000,000	3,868,000,000
Total	7,457,000,000	8,720,000,000
Liabilities of Consolidated VIEs
Other secured financings	5,944,000,000	6,705,000,000
Payables to customers and counterparties	60,000,000	12,000,000
Financial Instruments Sold, Not yet Purchased, at Fair Value	58,000,000	55,000,000
Unsecured short-term borrowings, including the current portion of unsecured long-term borrowings	2,136,000,000	2,661,000,000
Unsecured long-term borrowings	173,000,000	6,000,000
Other liabilities and accrued expenses	2,028,000,000	2,036,000,000
Total	10,399,000,000	11,475,000,000
Retained Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	5,666,000,000	6,949,000,000
Purchased Interests, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	1,796,000,000	1,439,000,000
Commitments and Guarantees, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	375,000,000	195,000,000
Derivatives, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	12,032,000,000	11,826,000,000
Loans and Investments, Maximum Exposure to Loss [Member]
Maximum Exposure to Loss, Non Consolidated VIE
Maximum Exposure to Loss in Nonconsolidated VIEs	$ 1,806,000,000	$ 1,411,000,000