DERIVATIVES ACTIVITIES - Gains (Losses) Included in Other Revenue (Details) - Other revenue - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative gain (losses)
Gains (losses) included in Other revenue	$ (377)	$ 1,451	$ (1,970)
Interest rate contracts
Derivative gain (losses)
Gains (losses) included in Other revenue	(25)	(73)	51
Foreign exchange contracts
Derivative gain (losses)
Gains (losses) included in Other revenue	(197)	2,062	(847)
Credit derivatives
Derivative gain (losses)
Gains (losses) included in Other revenue	$ (155)	$ (538)	$ (1,174)

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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