LOAN SERVICING RIGHTS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets [Line Items]
Servicing fees	$ 56,000	$ 37,200	$ 19,900
Residential mortgage
Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets [Line Items]
Servicing fees	51,400	31,100	14,000
SBA
Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets [Line Items]
Servicing fees	4,000	4,400	3,600
Indirect automobile
Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets [Line Items]
Servicing fees	$ 616	$ 1,700	$ 2,300