ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 15,393	$ 21,638	$ 16,455	$ 24,956
Gross credit losses on loans	(1,212)	(1,844)	(2,452)	(4,052)
Gross recoveries on loans	362	524	730	984
Net credit losses on loans (NCLs)	(850)	(1,320)	(1,722)	(3,068)
Net reserve builds (releases) for loans	520	(2,184)	(260)	(5,252)
Net specific reserve builds (releases) for loans	14	(262)	182	(421)
Total provision for credit losses on loans (PCLL)	1,384	(1,126)	1,644	(2,605)
Other, net (see table below)	25	46	(425)	(45)
ACLL at end of period	15,952	19,238	15,952	19,238
Allowance for credit losses on unfunded commitments
Allowance for credit losses on unfunded commitments (ACLUC) at beginning of period	2,343	2,012	1,871	2,655
Provision (release) for credit losses on unfunded lending commitments	(159)	44	315	(582)
Other, net	9	17	7	0
ACLUC at end of period	2,193	2,073	2,193	2,073
Total allowance for credit losses on loans, leases and unfunded lending commitments	18,145	21,311	18,145	21,311
Sales or transfers of various consumer loan portfolios to HFS
Reclasses of consumer ACLL to HFS	0	0	(350)	0
FX translation and other	25	46	(75)	(45)
Other, net	$ 25	$ 46	$ (425)	$ (45)