FAIR VALUE MEASUREMENT - Items Measured at Fair Value on a Nonrecurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Items Measured at Fair Value on a Nonrecurring Basis
Non-marketable equity securities measured using the measurement alternative	$ 7,749	$ 8,040
Nonrecurring | Level 2
Items Measured at Fair Value on a Nonrecurring Basis
Loans HFS	2,544	457
Other real estate owned	0	0
Loans	0	0
Non-marketable equity securities measured using the measurement alternative	0	0
Total assets	2,544	457
Nonrecurring | Level 3
Items Measured at Fair Value on a Nonrecurring Basis
Loans HFS	1,382	1,879
Other real estate owned	5	1
Loans	56	69
Non-marketable equity securities measured using the measurement alternative	158	597
Total assets	1,601	2,546
Fair value | Nonrecurring
Items Measured at Fair Value on a Nonrecurring Basis
Loans HFS	3,926	2,336
Other real estate owned	5	1
Loans	56	69
Non-marketable equity securities measured using the measurement alternative	158	597
Total assets	$ 4,145	$ 3,003