SEGMENT INFORMATION - Reconciliation of total segment operating noninterest expenses to total consolidated noninterest expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting, Reconciling Item for Non Interest Expenses from Segment to Consolidated [Line Items]
Operating noninterest expenses	$ 118,084	$ 114,052
Amortization of intangible assets	(3,576)	(3,667)
Merger and acquisition integration related (recoveries) expenses	35	57
Litigation accrual	(119)	0
Operating Segment
Segment Reporting, Reconciling Item for Non Interest Expenses from Segment to Consolidated [Line Items]
Operating noninterest expenses	115,603	111,563
Inter segment elimination
Segment Reporting, Reconciling Item for Non Interest Expenses from Segment to Consolidated [Line Items]
Operating noninterest expenses	$ (1,249)	$ (1,235)