VARIABLE INTEREST ENTITIES - Schedule of Assets and Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Variable Interest Entity [Line Items]
Total Assets	$ 45,896	$ 46,158	$ 44,146
Total Liabilities	39,890	40,108
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Total Assets	205	186
Total Liabilities	152	141
Maximum Exposure to Loss	202	183
Variable Interest Entity, Primary Beneficiary | Trust preferred securities
Variable Interest Entity [Line Items]
Total Assets	3	3
Total Liabilities	73	73
Maximum Exposure to Loss	0	0
Variable Interest Entity, Primary Beneficiary | Tax credit partnerships
Variable Interest Entity [Line Items]
Total Assets	174	143
Total Liabilities	79	62
Maximum Exposure to Loss	174	143
Variable Interest Entity, Primary Beneficiary | Other investments
Variable Interest Entity [Line Items]
Total Assets	28	40
Total Liabilities	0	6
Maximum Exposure to Loss	$ 28	$ 40