Collateralized Transactions (Gross Secured Financing Balances) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Gross Secured Financing Balances
Securities sold under agreements to repurchase	$ 114,653	$ 135,561
Securities loaned	30,276	20,542
Gross amount of secured financing included in the offseting disclosure	144,929	156,103
Trading liabilities: Obligation to return securities received as collateral	21,481	20,262
Total	166,410	176,365
U.S. Government and Agency Securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	28,512	56,372
State and Municipal Securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	157	1,363
Other Sovereign Government Obligations
Gross Secured Financing Balances
Securities sold under agreements to repurchase	51,498	42,790
Securities loaned	13,599	4,762
Asset-backed Securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	1,549	1,918
Corporate and Other Debt
Gross Secured Financing Balances
Securities sold under agreements to repurchase	5,083	9,086
Securities loaned	124	73
Corporate Equities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	26,599	23,152
Securities loaned	16,375	15,693
Trading liabilities: Obligation to return securities received as collateral	21,472	20,247
Other
Gross Secured Financing Balances
Securities sold under agreements to repurchase	1,255	880
Securities loaned	178	14
Trading liabilities: Obligation to return securities received as collateral	9	15
Overnight and Open
Gross Secured Financing Balances
Securities sold under agreements to repurchase	29,403	41,549
Securities loaned	16,447	9,487
Gross amount of secured financing included in the offseting disclosure	45,850	51,036
Trading liabilities: Obligation to return securities received as collateral	21,481	20,262
Total	67,331	71,298
Less than 30 days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	26,884	36,703
Securities loaned	1,656	851
Gross amount of secured financing included in the offseting disclosure	28,540	37,554
Trading liabilities: Obligation to return securities received as collateral	0	0
Total	28,540	37,554
30-90 days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	18,896	24,648
Securities loaned	1,833	2,863
Gross amount of secured financing included in the offseting disclosure	20,729	27,511
Trading liabilities: Obligation to return securities received as collateral	0	0
Total	20,729	27,511
Over 90 days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	39,470	32,661
Securities loaned	10,340	7,341
Gross amount of secured financing included in the offseting disclosure	49,810	40,002
Trading liabilities: Obligation to return securities received as collateral	0	0
Total	$ 49,810	$ 40,002

The aggregate amount of liabilities as of the balance sheet date for obligations incurred in connection with the entity's investments.

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The fair value of collateral received by the entity associated with securities borrowed that must be returned if the counterparty fulfills its obligations. It appears on the balance sheet as a liability and has a corresponding asset that appears on the balance sheet called Securities Received as Collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Repurchase Agreement Accounted for as a Collateralized Borrowing
-URI http://asc.fasb.org/extlink&oid=49203159

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