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Collateralized Transactions (Amounts Related to Collateralized Transactions) (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
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Permitted To Repledge [Member] |  |  |
Collateralized Transactions [Line Items] |  |  |
Securities lending transactions |  | $ 28,591 | $ 21,412
Agreements to resell | [1] | 18,885 | 12,672
Customer margin assets |  | 26,060 | 25,778
Total collateralized transactions |  | 73,536 | 59,862
Sold Or Repledged [Member] |  |  |
Collateralized Transactions [Line Items] |  |  |
Securities lending transactions |  | 4,078 | 3,284
Agreements to resell | [1] | 18,081 | 11,881
Customer margin assets |  | 9,707 | 6,616
Total collateralized transactions |  | $ 31,866 | $ 21,781
[1] | As of September 30, 2019, $17.5 billion or 97% (as of December 31, 2018, $11.4 billion or 96%) 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 Market value of collateral received in reverse repurchase transactions + References No definition available. + Details
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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 Market value of collateral received in securities lending transactions + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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- Details
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- Details
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