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Collateralized Transactions (Amounts Related to Collateralized Transactions) (Details) - USD ($) $ in Millions | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Permitted To Repledge [Member] |  |  |
Collateralized Transactions [Line Items] |  |  |
Securities lending transactions |  | $ 11,809 | $ 12,131
Agreements to resell | [1] | 4,724 | 757
Customer margin assets |  | 13,806 | 14,905
Total collateralized transactions |  | 30,339 | 27,793
Sold Or Repledged [Member] |  |  |
Collateralized Transactions [Line Items] |  |  |
Securities lending transactions |  | 3,743 | 2,229
Agreements to resell | [1] | 4,724 | 743
Customer margin assets |  | 6,989 | 6,279
Total collateralized transactions |  | $ 15,456 | $ 9,251
[1] | As of June 30, 2016, $4.6 billion or 98% (as of December 31, 2015, $0.6 billion or 76%) of securities acquired through agreements to resell that are shown as repledged have been deposited in a separate bank account for the exclusive benefit of customers in accordance with SEC Rule 15c3-3.

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- Definition Collateralized Transactions [Line Items] + References No definition available. + Details
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- Definition Total market value of collateralized transactions as of the balance sheet date. + References No definition available. + Details
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- Definition Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729 + Details
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- Details
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