Collateralized Transactions (Secured Financing Transactions) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Securities Financing Transaction
Securities sold under agreements to repurchase	$ 102,311	$ 84,749
Securities loaned	22,989	24,387
Gross amount of secured financing included in the above offseting disclosure	125,300	109,136
Obligation to return securities received as collateral	17,984	19,316
Total	143,284	128,452
U.S. Government and Agency Securities
Securities Financing Transaction
Securities sold under agreements to repurchase	42,323	36,609
Securities loaned	34	0
State And Municipal Securities
Securities Financing Transaction
Securities sold under agreements to repurchase	1,151	173
Other Sovereign Government Obligations
Securities Financing Transaction
Securities sold under agreements to repurchase	31,765	24,820
Securities loaned	5,907	7,336
Asset-backed Securities
Securities Financing Transaction
Securities sold under agreements to repurchase	356	441
Corporate and Other Debt
Securities Financing Transaction
Securities sold under agreements to repurchase	6,283	4,020
Securities loaned	91	71
Obligation to return securities received as collateral	0	3
Corporate Equities
Securities Financing Transaction
Securities sold under agreements to repurchase	19,740	18,473
Securities loaned	16,935	16,972
Obligation to return securities received as collateral	17,981	19,313
Other
Securities Financing Transaction
Securities sold under agreements to repurchase	693	213
Securities loaned	22	8
Obligation to return securities received as collateral	3	0
Overnight and Open
Securities Financing Transaction
Securities sold under agreements to repurchase	36,220	20,410
Securities loaned	11,911	12,247
Gross amount of secured financing included in the above offseting disclosure	48,131	32,657
Obligation to return securities received as collateral	17,984	19,316
Total	66,115	51,973
Less than 30 days
Securities Financing Transaction
Securities sold under agreements to repurchase	18,088	25,245
Securities loaned	866	478
Gross amount of secured financing included in the above offseting disclosure	18,954	25,723
Obligation to return securities received as collateral	0	0
Total	18,954	25,723
30-90 days
Securities Financing Transaction
Securities sold under agreements to repurchase	20,689	13,221
Securities loaned	2,241	2,156
Gross amount of secured financing included in the above offseting disclosure	22,930	15,377
Obligation to return securities received as collateral	0	0
Total	22,930	15,377
Over 90 days
Securities Financing Transaction
Securities sold under agreements to repurchase	27,314	25,873
Securities loaned	7,971	9,506
Gross amount of secured financing included in the above offseting disclosure	35,285	35,379
Obligation to return securities received as collateral	0	0
Total	$ 35,285	$ 35,379

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
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Collateral
-URI http://asc.fasb.org/extlink&oid=6507830

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+ References

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)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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