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Collateralized Transactions (Tables) | 12 Months Ended
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Dec. 31, 2017
Disclosure Collateralized Transactions [Abstract] |
Amounts Related To Collateralized Transactions |
﻿ |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  | December 31, 2017 |  | December 31, 2016
﻿ |  | Permitted |  | Sold or |  | Permitted |  | Sold or
﻿ |  | to Repledge |  | Repledged |  | to Repledge |  | Repledged
﻿ |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  | (in millions)
﻿Securities lending transactions |  | $ | 23,662 |  | $ | 3,041 |  | $ | 13,768 |  | $ | 3,621
﻿Securities purchased under agreements to resell transactions (1) |  |  | 11,231 |  |  | 11,231 |  |  | 11,117 |  |  | 11,117
﻿Customer margin assets |  |  | 30,236 |  |  | 9,013 |  |  | 17,773 |  |  | 7,172
﻿ |  | $ | 65,129 |  | $ | 23,285 |  | $ | 42,658 |  | $ | 21,910
﻿
| (1) |  | As of December 31, 2017, $9.2 billion or 82% (as of December 31, 2016, $11.0 billion or 99%) 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.
Financial Instruments Owned and Pledged as Collateral (table) |
﻿ |  |  |  |  |  |
﻿ |  |  |  |  |  |
﻿ |  | December 31, |  | December 31,
﻿ |  | 2017 |  | 2016
﻿ |  |  |  |  |  |
﻿ |  | (in millions)
﻿Stocks |  | $ | 1,150 |  | $ | 1,574
﻿U.S. and foreign government securities |  |  | 54 |  |  | 359
﻿ |  | $ | 1,204 |  | $ | 1,933
﻿

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- Definition Tabular disclosure of financial instruments held by the entity for its own account for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. Description may include equity, fixed income, debt or other securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=64858031&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=66007379&loc=d3e113888-111728 + Details
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