FAIR VALUE MEASUREMENTS - Schedule of Fair Value Measurements on a Nonrecurring Basis (Details) - Nonrecurring measurement basis - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent loans	$ 645	$ 758
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent loans	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent loans	645	758
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent loans	$ 0	$ 0