Commitments, Pledged Assets, and Collateral - Pledged Assets and Collateral (Details) (USD $) In Billions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Significant components of assets pledged
Significant components of assets pledged as collateral, fair value	$ 535.9	$ 461.7
Financial instruments pledged by the Firm that may not be sold or repledged by the secured parties	60.1	68.4
Collateral Received that Can be Resold or Repledged
Assets accepted by the Firm as collateral that it could sell or repedge, deliver or otherwise use at fair value	761.7	725.0
Assets accepted by the Firm as collateral that the Firm has sold or repledged	596.8	520.1
Asset-backed securities
Significant components of assets pledged
Significant components of assets pledged as collateral, fair value	118.7	68.1
Loans
Significant components of assets pledged
Significant components of assets pledged as collateral, fair value	248.2	230.3
Trading assets
Significant components of assets pledged
Significant components of assets pledged as collateral, fair value	169.0	163.3
Assets pledged to Federal Reserve Banks and Federal Home Loan Banks
Significant components of assets pledged
Significant components of assets pledged as collateral, fair value	$ 324.5	$ 251.3

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Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions where counterparty does not have the right to re-pledge such.

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)(1)(i)

-URI http://asc.fasb.org/extlink&oid=34720971&loc=SL6224234-111729

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6467456&loc=d3e113888-111728

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