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LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023		Dec. 31, 2022	Dec. 31, 2021
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	$ 36,515		$ 35,273	$ 49,006
Loans charged-off	(4,204)	[1]	(2,584)	(2,751)
Recoveries of loans charged-off	1,454		1,888	1,980
Net loans (charged-off) recovered	(2,750)		(696)	(771)
Provision for (reversal of) loan losses	8,909		1,938	(12,962)
Balance at end of period	42,674		36,515	35,273
Construction real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	3,164		3,787	6,490
Loans charged-off	(92)		0	0
Recoveries of loans charged-off	2		2	2
Net loans (charged-off) recovered	(90)		2	2
Provision for (reversal of) loan losses	2,213		(625)	(2,705)
Balance at end of period	5,287		3,164	3,787
1-4 family residential real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	2,173		1,866	2,270
Loans charged-off	(119)		(69)	(136)
Recoveries of loans charged-off	110		107	75
Net loans (charged-off) recovered	(9)		38	(61)
Provision for (reversal of) loan losses	676		269	(343)
Balance at end of period	2,840		2,173	1,866
Commercial real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	28,701		26,980	35,709
Loans charged-off	(788)	[1]	0	0
Recoveries of loans charged-off	1		81	87
Net loans (charged-off) recovered	(787)		81	87
Provision for (reversal of) loan losses	4,352		1,640	(8,816)
Balance at end of period	32,266		28,701	26,980
Commercial real estate loans | Commercial and Industrial Sector
Allowance for Loan Losses [Roll Forward]
Loans charged-off	(788)
Reclassification to held-for-sale	8,100
Commercial loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	2,235		2,397	4,107
Loans charged-off	(1,283)		(792)	(1,004)
Recoveries of loans charged-off	298		593	674
Net loans (charged-off) recovered	(985)		(199)	(330)
Provision for (reversal of) loan losses	836		37	(1,380)
Balance at end of period	2,086		2,235	2,397
Municipal loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	45		47	46
Loans charged-off	0		0	0
Recoveries of loans charged-off	0		0	0
Net loans (charged-off) recovered	0		0	0
Provision for (reversal of) loan losses	(26)		(2)	1
Balance at end of period	19		45	47
Loans to individuals
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	197		196	384
Loans charged-off	(1,922)		(1,723)	(1,611)
Recoveries of loans charged-off	1,043		1,105	1,142
Net loans (charged-off) recovered	(879)		(618)	(469)
Provision for (reversal of) loan losses	858		619	281
Balance at end of period	$ 176		$ 197	$ 196
[1] Included in charge-offs for the year ended December 31, 2023 is a $788,000 write down to fair value an $8.1 million commercial real estate loan relationship transferred to held for sale.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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