OPERATING SEGMENTS - Segment Information (Details) - USD ($) $ in Millions							3 Months Ended	12 Months Ended
		Aug. 12, 2023	Mar. 01, 2023	Nov. 01, 2022	Aug. 01, 2022	Jun. 01, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net interest income								$ 54,900	$ 48,668	$ 42,494
Non-interest revenue								23,562	26,670	29,390
Operating expense								56,366	51,292	48,193
Total revenues, net of interest expense								78,462	75,338	71,884
Provision (benefits) for income taxes								3,528	3,642	5,451
Income (loss) from continuing operations								9,382	15,165	22,018
Identifiable assets								2,411,834	2,416,676	2,291,000
Average loans								661,000	653,000	668,000
Average deposits								1,334,000	1,333,000	1,335,000
Provisions for credit losses and for benefits and claims	[1]							9,186	5,239	(3,778)
Goodwill impairment							$ 535	0	535	0
Goodwill impairment, after-tax							$ 489
Discontinued Operations, Disposed of by Sale | India Consumer Banking Business
Segment Reporting Information [Line Items]
Pretax loss on sale			$ (1,100)					(1,059)
Loss on sale, after-tax			$ (727)					(727)
Discontinued Operations, Disposed of by Sale | Taiwan Consumer Banking Business
Segment Reporting Information [Line Items]
Pretax loss on sale		$ (403)						(403)
Loss on sale, after-tax		$ (284)						(284)
Discontinued Operations, Disposed of by Sale | Philippines Consumer Banking Business
Segment Reporting Information [Line Items]
Pretax loss on sale					$ (618)				(616)
Loss on sale, after-tax					$ (290)				(290)
Discontinued Operations, Disposed of by Sale | Thailand Consumer Banking Business
Segment Reporting Information [Line Items]
Pretax loss on sale				$ (209)					(209)
Loss on sale, after-tax				$ (115)					(115)
Discontinued Operations, Disposed of by Sale | Australia Consumer Banking Business
Segment Reporting Information [Line Items]
Pretax loss on sale						$ 766				680
Loss on sale, after-tax						$ 643				580
Discontinued Operations, Disposed of by Sale | Korea Consumer Banking Business
Segment Reporting Information [Line Items]
Operating expenses, before tax										1,052
Operating expenses, after tax										792
Discontinued Operations, Disposed of by Sale | Asia Consumer Banking Business
Segment Reporting Information [Line Items]
Goodwill impairment									535
Goodwill impairment, after-tax									489
Discontinued Operations, Held-for-sale | Mexico and Asia Exit Markets
Segment Reporting Information [Line Items]
Operating expenses, before tax								372
Operating expenses, after tax								263
North America
Segment Reporting Information [Line Items]
Total revenues, net of interest expense								36,661	34,799	35,022
Identifiable assets								1,348,169	1,306,127
International
Segment Reporting Information [Line Items]
Total revenues, net of interest expense								39,636	39,018	36,037
Identifiable assets								930,185	979,214
Corporate/Other
Segment Reporting Information [Line Items]
Total revenues, net of interest expense								2,165	1,521	825
Identifiable assets								133,480	131,335
U.K.
Segment Reporting Information [Line Items]
Total revenues, net of interest expense								7,600	9,200	7,400
Markets
Segment Reporting Information [Line Items]
Provisions for credit losses and for benefits and claims								437	155	(329)
Operating Segments
Segment Reporting Information [Line Items]
Income (loss) from continuing operations								8,723	15,349	23,660
Operating Segments | Services
Segment Reporting Information [Line Items]
Net interest income								13,198	10,318	6,821
Non-interest revenue								4,852	5,301	5,702
Total revenues, net of interest expense								18,050	15,619	12,523
Provision (benefits) for income taxes								2,405	1,760	1,312
Income (loss) from continuing operations								4,671	4,924	3,768
Identifiable assets								585,000	599,000	547,000
Average loans								81,000	82,000	74,000
Average deposits								810,000	808,000	805,000
Provisions for credit losses and for benefits and claims								950	207	(263)
Goodwill impairment									0
Operating Segments | Markets
Segment Reporting Information [Line Items]
Net interest income								7,265	5,819	6,147
Non-interest revenue								11,592	14,342	13,252
Total revenues, net of interest expense								18,857	20,161	19,399
Provision (benefits) for income taxes								1,162	1,669	1,695
Income (loss) from continuing operations								4,020	5,924	6,661
Identifiable assets								995,000	950,000	895,000
Average loans								110,000	111,000	112,000
Average deposits								23,000	21,000	22,000
Goodwill impairment									0
Operating Segments | Banking
Segment Reporting Information [Line Items]
Net interest income								2,094	2,057	2,204
Non-interest revenue								2,474	3,339	5,579
Total revenues, net of interest expense								4,568	5,396	7,783
Provision (benefits) for income taxes								(92)	(7)	1,170
Income (loss) from continuing operations								(44)	383	4,105
Identifiable assets								147,000	152,000	145,000
Average loans								90,000	98,000	101,000
Average deposits								1,000	1,000	1,000
Provisions for credit losses and for benefits and claims								(165)	549	(1,898)
Goodwill impairment									0
Operating Segments | USPB
Segment Reporting Information [Line Items]
Net interest income								20,150	18,062	16,285
Non-interest revenue								(963)	(1,190)	(440)
Total revenues, net of interest expense								19,187	16,872	15,845
Provision (benefits) for income taxes								558	872	1,890
Income (loss) from continuing operations								1,820	2,770	6,099
Identifiable assets								242,000	231,000	211,000
Average loans								193,000	171,000	159,000
Average deposits								110,000	115,000	112,000
Provisions for credit losses and for benefits and claims								6,707	3,448	(998)
Goodwill impairment									0
Operating Segments | Wealth
Segment Reporting Information [Line Items]
Net interest income								4,460	4,744	4,491
Non-interest revenue								2,631	2,704	3,051
Total revenues, net of interest expense								7,091	7,448	7,542
Provision (benefits) for income taxes								103	134	419
Income (loss) from continuing operations								346	950	1,968
Identifiable assets								232,000	259,000	250,000
Average loans								150,000	150,000	148,000
Average deposits								316,000	320,000	305,000
Provisions for credit losses and for benefits and claims								(2)	306	(226)
Goodwill impairment									0
All Other
Segment Reporting Information [Line Items]
Net interest income								7,733	7,668	6,546
Non-interest revenue								1,630	1,320	2,916
Total revenues, net of interest expense								9,363	8,988	9,462
Provision (benefits) for income taxes								(990)	(1,052)	(812)
Income (loss) from continuing operations								(2,090)	398	1,059
Identifiable assets								211,000	226,000	243,000
Average loans								37,000	41,000	74,000
Average deposits								74,000	68,000	90,000
Provisions for credit losses and for benefits and claims								1,326	498	(88)
Goodwill impairment									535
Reconciling Items
Segment Reporting Information [Line Items]
Net interest income								0	0	0
Non-interest revenue								1,346	854	(670)
Operating expense								372	696	1,171
Provision for credit losses on loans								(67)	76	24
Total revenues, net of interest expense								1,346	854	(670)
Provision (benefits) for income taxes								382	266	(223)
Income (loss) from continuing operations								659	(184)	(1,642)
Provisions for credit losses and for benefits and claims								$ (67)	$ 76	$ 24

[1] This total excludes the provision for credit losses on AFS securities, which is disclosed separately above.