CREDIT QUALITY ASSESSMENT - Information on the Credit Quality of Loan Portfolio (Details) - Non-accrual status - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 91,485	$ 34,782
Loans placed on non-accrual	1,490	81,877
Non-accrual balances transferred to OREO	(2,700)	0
Non-accrual balances charged-off	(1,550)	(2,358)
Net payments or draws	(4,017)	(21,030)
Non-accrual loans brought current	(627)	(1,786)
Balance at end of period	84,081	91,485
Commercial real estate: | Commercial investor real estate
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	58,658	9,943
Loans placed on non-accrual	715	62,725
Non-accrual balances transferred to OREO	(2,700)	0
Non-accrual balances charged-off	(1)	0
Net payments or draws	(1,093)	(14,010)
Non-accrual loans brought current	0	0
Balance at end of period	55,579	58,658
Commercial real estate: | Commercial owner-occupied real estate
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	4,640	5,019
Loans placed on non-accrual	0	0
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	(246)	(379)
Non-accrual loans brought current	0	0
Balance at end of period	4,394	4,640
Commercial real estate: | Commercial AD&C
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	1,259	0
Loans placed on non-accrual	0	2,111
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	(703)	(852)
Non-accrual loans brought current	0	0
Balance at end of period	556	1,259
Commercial Business
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	10,051	7,322
Loans placed on non-accrual	25	6,271
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	(1,549)	(441)
Net payments or draws	(1,363)	(2,588)
Non-accrual loans brought current	0	(513)
Balance at end of period	7,164	10,051
Residential real estate: | Residential mortgage
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	12,332	7,439
Loans placed on non-accrual	362	7,871
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	(160)
Net payments or draws	(288)	(1,667)
Non-accrual loans brought current	(571)	(1,151)
Balance at end of period	11,835	12,332
Residential real estate: | Residential construction
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	443	0
Loans placed on non-accrual	0	449
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	99	(6)
Non-accrual loans brought current	0	0
Balance at end of period	542	443
Consumer
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	4,102	5,059
Loans placed on non-accrual	388	2,450
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	(1,757)
Net payments or draws	(423)	(1,528)
Non-accrual loans brought current	(56)	(122)
Balance at end of period	$ 4,011	$ 4,102