GOODWILL AND INTANGIBLE ASSETS - Changes in Goodwill (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2025	Mar. 31, 2025
Goodwill
Balance at December 31, 2024	$ 19,422	$ 19,300
Foreign currency translation	456	122
Balance at June 30, 2025	19,878	19,422
All Other
Goodwill
Balance at December 31, 2024	919	902
Foreign currency translation	83	17
Balance at June 30, 2025	1,002	919
Services \| Operating Segments
Goodwill
Balance at December 31, 2024	2,063	2,052
Foreign currency translation	109	11
Balance at June 30, 2025	2,172	2,063
Markets \| Operating Segments
Goodwill
Balance at December 31, 2024	5,749	5,674
Foreign currency translation	171	75
Balance at June 30, 2025	5,920	5,749
Banking \| Operating Segments
Goodwill
Balance at December 31, 2024	1,005	1,002
Foreign currency translation	20	3
Balance at June 30, 2025	1,025	1,005
USPB \| Operating Segments
Goodwill
Balance at December 31, 2024	5,235	5,219
Foreign currency translation	71	16
Balance at June 30, 2025	5,306	5,235
Wealth \| Operating Segments
Goodwill
Balance at December 31, 2024	4,451	4,451
Foreign currency translation	2	0
Balance at June 30, 2025	$ 4,453	$ 4,451

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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