ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 17,169	$ 15,393	$ 16,974	$ 16,455
Gross credit losses on loans	(1,879)	(1,212)	(3,513)	(2,452)
Gross recoveries on loans	375	362	707	730
Net credit losses on loans (NCLs)	(1,504)	(850)	(2,806)	(1,722)
Net reserve builds (releases) for loans	290	520	687	(260)
Net specific reserve builds (releases) for loans	(33)	14	5	182
Total provision for credit losses on loans (PCLL)	1,761	1,384	3,498	1,644
Other, net (see table below)	70	25	182	(425)
ACLL at end of period	17,496	15,952	17,496	15,952
Allowance for credit losses on unfunded commitments
Allowance for credit losses on unfunded commitments (ACLUC) at beginning of period	1,959	2,343	2,151	1,871
Provision (release) for credit losses on unfunded lending commitments	(96)	(159)	(290)	315
Other, net	(1)	9	1	7
ACLUC at end of period	1,862	2,193	1,862	2,193
Total allowance for credit losses on loans, leases and unfunded lending commitments	19,358	18,145	19,358	18,145	$ 19,125
Sales or transfers of various consumer loan portfolios to HFS
Reclasses of consumer ACLL to HFS	0	0	0	(350)
FX translation and other	70	25	182	(75)
Other, net	70	25	182	(425)
Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	0	0	(352)	0
Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 17,169	$ 15,393	$ 16,622	$ 16,455