FAIR VALUE MEASURES - Loans Held for Sale Under the Fair Value Option (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 901,550	$ 1,254,632
Mortgage loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	899,009	1,247,997
SBA loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 2,541	$ 6,635