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Financial Assets And Financial Liabilities (Trading Gains from Market Making Transactions) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Financial Assets And Financial Liabilities [Abstract] |  |  |
Equities | $ 42 | $ 155 | $ 254
Fixed Income |  |  | 1
Foreign exchange | (2) | 8 | 14
Total trading gains, net | $ 40 | $ 163 | $ 269

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- Definition Trading Gains from Equities + References No definition available. + Details
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- Definition Trading Gains from Fixed Income + References No definition available. + Details
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- Definition Trading Gains Foreign Exchange + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(e)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 35 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42454-110968 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42567-110969 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4F -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624186-113959 + Details
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