SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Carrying Amounts and Classifications of Consolidated Assets (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Variable Interest Entity
Cash	$ 25,174	$ 27,342	$ 26,224
Trading account assets	431,468	411,756
Investments	515,183	519,085
Other assets	97,701	95,963
Total assets	2,432,510	2,411,834
Unconsolidated VIEs
Variable Interest Entity
Cash	0	0
Trading account assets	4,200	1,900
Investments	5,800	8,300
Total loans, net of allowance	49,600	51,800
Other assets	600	600
Total assets	$ 60,200	$ 62,600