ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 15,952	$ 19,238	$ 16,455	$ 24,956
Gross credit losses on loans	(1,237)	(1,389)	(3,689)	(5,441)
Gross recoveries on loans	350	428	1,080	1,412
Net credit losses on loans (NCLs)	(887)	(961)	(2,609)	(4,029)
Net reserve builds (releases) for loans	519	(1,010)	259	(6,262)
Net specific reserve builds (releases) for loans	(78)	(139)	104	(560)
Total provision for credit losses on loans (PCLL)	1,328	(188)	2,972	(2,793)
Other, net (see table below)	(84)	(374)	(509)	(419)
ACLL at end of period	16,309	17,715	16,309	17,715
Allowance for credit losses on unfunded commitments
Allowance for credit losses on unfunded commitments (ACLUC) at beginning of period	2,193	2,073	1,871	2,655
Provision (release) for credit losses on unfunded lending commitments	(71)	(13)	244	(595)
Other, net	(33)	3	(26)	3
ACLUC at end of period	2,089	2,063	2,089	2,063
Total allowance for credit losses on loans, leases and unfunded lending commitments	18,398	19,778	18,398	19,778
Sales or transfers of various consumer loan portfolios to HFS
Reclasses of consumer ACLL to HFS	0	(278)	(350)	(278)
FX translation and other	(84)	(96)	(159)	(141)
Other, net	$ (84)	$ (374)	$ (509)	$ (419)