Variable Interest Entities - Firm Sponsored Variable Interest Entities (Details 0) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	$ 283,800,000,000	$ 295,800,000,000
Firm-sponsored credit card securitization trusts
Percentage of the Firm's retained securitization interests risk-rated 'A' or better, at fair value	69.00%	74.00%
Investment Bank
Firm-sponsored credit card securitization trusts
Senior Securities Purchased, Excluded from Interests Continued To Be Held By Transferor, Fair Value	276,000,000	131,000,000
Subordinated Securities Purchased, Excluded From Interests Continued To Be Held by Transferor, Fair Value	12,000,000	45,000,000
Prime
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	96,400,000,000	107,200,000,000
Prime \| Investment Grade A or Better
Firm-sponsored credit card securitization trusts
Retained Interest, Fair Value Disclosure	418,000,000	170,000,000
Prime \| Noninvestment-grade
Firm-sponsored credit card securitization trusts
Retained Interest, Fair Value Disclosure	284,000,000	171,000,000
Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	33,700,000,000	34,500,000,000
Option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	24,500,000,000	26,300,000,000
Commercial mortgage
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	129,200,000,000	127,800,000,000
Commercial mortgage \| Investment Grade A or Better
Firm-sponsored credit card securitization trusts
Retained Interest, Fair Value Disclosure	3,700,000,000	4,100,000,000
Commercial mortgage \| Noninvestment-grade
Firm-sponsored credit card securitization trusts
Retained Interest, Fair Value Disclosure	163,000,000	164,000,000
Variable Interest Entity, Primary Beneficiary
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	3,800,000,000	4,000,000,000
Variable Interest Entity, Primary Beneficiary \| Prime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	2,500,000,000	2,500,000,000
Variable Interest Entity, Primary Beneficiary \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	1,100,000,000	1,300,000,000
Variable Interest Entity, Primary Beneficiary \| Option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	200,000,000	200,000,000
Variable Interest Entity, Primary Beneficiary \| Commercial mortgage
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	0	0
Variable Interest Entity, Not Primary Beneficiary
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	221,518,000,000	219,765,000,000
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	4,600,000,000	4,700,000,000
Variable Interest Entity, Not Primary Beneficiary \| Trading assets
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	1,800,000,000	1,900,000,000
Variable Interest Entity, Not Primary Beneficiary \| Available-for-sale Securities
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	2,800,000,000	2,800,000,000
Variable Interest Entity, Not Primary Beneficiary \| Prime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	74,919,000,000	80,572,000,000
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	700,000,000	300,000,000
Variable Interest Entity, Not Primary Beneficiary \| Prime \| Trading assets
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	500,000,000	300,000,000
Variable Interest Entity, Not Primary Beneficiary \| Prime \| Available-for-sale Securities
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	200,000,000	0
Variable Interest Entity, Not Primary Beneficiary \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	30,271,000,000	31,264,000,000
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	100,000,000	100,000,000
Variable Interest Entity, Not Primary Beneficiary \| Subprime \| Trading assets
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	100,000,000	100,000,000
Variable Interest Entity, Not Primary Beneficiary \| Subprime \| Available-for-sale Securities
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	0	0
Variable Interest Entity, Not Primary Beneficiary \| Option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	24,253,000,000	26,095,000,000
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	0	0
Variable Interest Entity, Not Primary Beneficiary \| Option ARMs \| Trading assets
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	0	0
Variable Interest Entity, Not Primary Beneficiary \| Option ARMs \| Available-for-sale Securities
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	0	0
Variable Interest Entity, Not Primary Beneficiary \| Commercial mortgage
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	92,075,000,000	81,834,000,000
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	3,800,000,000	4,300,000,000
Variable Interest Entity, Not Primary Beneficiary \| Commercial mortgage \| Trading assets
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	1,200,000,000	1,500,000,000
Variable Interest Entity, Not Primary Beneficiary \| Commercial mortgage \| Available-for-sale Securities
Firm-sponsored credit card securitization trusts
Interest in sponsored credit card securitization trusts	$ 2,600,000,000	$ 2,800,000,000

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- Definition

Percent of retained securitization interests rated A or better.

+ References

No definition available.

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- Definition

Senior securities purchased in connection with IB secondary market making activities. These securities are excluded from entity interest in securitized assets in nonconsolidated VIEs.

+ References

No definition available.

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- Definition

Subordinated securities purchased in connection with IB secondary market making Activities. These securities are excluded from entity interest in securitized assets in nonconsolidated VIEs.

+ References

No definition available.

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- Definition

The carrying amount (fair value) as of the balance sheet date of the transferor's interests in transferred financial assets (typically securitized receivables, generally not involved in the collection of principal) following transfer of significant portions of such financial instruments to other parties. Such interests could be ancillary cash flows and interest-only strips.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(3)

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-Paragraph B11

-Subparagraph b(5)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 17

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- Definition

This includes the recognized portion of the total principal amount of financial assets which have been either securitized, used in an asset-backed financing arrangement, or similar transfer which are accounted for as sales and in which the transferor has continuing involvement with the assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Paragraph 4

-Subparagraph (a)(3)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name FASB Staff Position (FSP)

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- Definition

This includes only the derecognized portion of the total principal amount of financial assets which have been either securitized, used in an asset-backed financing arrangement, or similar transfers which are accounted for as sales and in which the transferor has continuing involvement with the assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subclause a

-Clause 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name FASB Staff Position (FSP)

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- Definition

The total principal outstanding of financial assets transferred in a securitization, asset-backed financing arrangement, or similar transfer that has been accounted for as sales and in which the transferor continues to have involvement, including both the derecognized and recognized portion of such transferred assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph f

-Subclause a

-Clause 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

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-Name FASB Staff Position (FSP)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the interests continued to be held by a transferor (retained or residual interest) after transferring financial assets to a third party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 4, 58, 59

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 7

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