GOODWILL AND INTANGIBLE ASSETS - Changes in Goodwill (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill
Balance of goodwill at beginning of period	$ 22,126
Foreign currency translation	(862)
Balance of goodwill at end of period	21,264
Global Consumer Banking
Goodwill
Balance of goodwill at beginning of period	12,102
Foreign currency translation	(265)
Balance of goodwill at end of period	11,837
Institutional Clients Group
Goodwill
Balance of goodwill at beginning of period	10,024
Foreign currency translation	(597)
Balance of goodwill at end of period	$ 9,427

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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