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Financial Assets And Financial Liabilities (Trading Gains from Market Making Transactions) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financial Assets And Financial Liabilities [Abstract]
Equities	$ 39	$ 42	$ 155
Foreign exchange		(2)	8
Total trading gains, net	$ 39	$ 40	$ 163

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- Definition

Trading Gains from Equities

+ References

No definition available.

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- Definition

Trading Gains Foreign Exchange

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4F
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624186-113959

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-Section 35
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 220
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