GOODWILL AND INTANGIBLE ASSETS - Changes in Goodwill (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021
Goodwill
Balance of goodwill at beginning of period	$ 22,060	$ 21,905	$ 22,162
Foreign currency translation	(260)	155	(257)
Divestiture	(227)
Balance of goodwill at end of period	21,573	22,060	21,905
Global Consumer Banking
Goodwill
Balance of goodwill at beginning of period	12,108	12,074	12,142
Foreign currency translation	(87)	34	(68)
Divestiture	(227)
Balance of goodwill at end of period	11,794	12,108	12,074
Institutional Clients Group
Goodwill
Balance of goodwill at beginning of period	9,952	9,831	10,020
Foreign currency translation	(173)	121	(189)
Divestiture	0
Balance of goodwill at end of period	$ 9,779	$ 9,952	$ 9,831

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.

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