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LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($)		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	$ 24,797,000	$ 35,273,000	$ 49,006,000	$ 24,797,000
Impact of CECL adoption - purchased loans with credit deterioration	231,000
Loans charged-off		(2,584,000)	(2,751,000)	(2,854,000)
Recoveries of loans charged-off		1,888,000	1,980,000	1,650,000
Net loans (charged-off) recovered		(696,000)	(771,000)	(1,204,000)
Provision for (reversal of) loan losses		1,938,000	(12,962,000)	20,110,000	[1]
Balance at end of period		36,515,000	35,273,000	49,006,000
Construction real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	3,539,000	3,787,000	6,490,000	3,539,000
Loans charged-off		0	0	(40,000)
Recoveries of loans charged-off		2,000	2,000	28,000
Net loans (charged-off) recovered		2,000	2,000	(12,000)
Provision for (reversal of) loan losses		(625,000)	(2,705,000)	10,000	[1]
Balance at end of period		3,164,000	3,787,000	6,490,000
1-4 family residential real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	3,833,000	1,866,000	2,270,000	3,833,000
Loans charged-off		(69,000)	(136,000)	(152,000)
Recoveries of loans charged-off		107,000	75,000	32,000
Net loans (charged-off) recovered		38,000	(61,000)	(120,000)
Provision for (reversal of) loan losses		269,000	(343,000)	10,000	[1]
Balance at end of period		2,173,000	1,866,000	2,270,000
Commercial real estate loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	9,572,000	26,980,000	35,709,000	9,572,000
Loans charged-off		0	0	(33,000)
Recoveries of loans charged-off		81,000	87,000	102,000
Net loans (charged-off) recovered		81,000	87,000	69,000
Provision for (reversal of) loan losses		1,640,000	(8,816,000)	18,005,000	[1]
Balance at end of period		28,701,000	26,980,000	35,709,000
Commercial loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	6,351,000	2,397,000	4,107,000	6,351,000
Loans charged-off		(792,000)	(1,004,000)	(823,000)
Recoveries of loans charged-off		593,000	674,000	310,000
Net loans (charged-off) recovered		(199,000)	(330,000)	(513,000)
Provision for (reversal of) loan losses		37,000	(1,380,000)	1,823,000	[1]
Balance at end of period		2,235,000	2,397,000	4,107,000
Municipal loans
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	570,000	47,000	46,000	570,000
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		(2,000)	1,000	(2,000)	[1]
Balance at end of period		45,000	47,000	46,000
Loans to individuals
Allowance for Loan Losses [Roll Forward]
Balance at beginning of period	$ 932,000	196,000	384,000	932,000
Loans charged-off		(1,723,000)	(1,611,000)	(1,806,000)
Recoveries of loans charged-off		1,105,000	1,142,000	1,178,000
Net loans (charged-off) recovered		(618,000)	(469,000)	(628,000)
Provision for (reversal of) loan losses		619,000	281,000	264,000	[1]
Balance at end of period		$ 197,000	$ 196,000	384,000
Impact of CECL adoption
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				5,072,000
Impact of CECL adoption - purchased loans with credit deterioration				231,000
Impact of CECL adoption | Construction real estate loans
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				2,968,000
Impact of CECL adoption - purchased loans with credit deterioration				(15,000)
Impact of CECL adoption | 1-4 family residential real estate loans
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				(1,447,000)
Impact of CECL adoption - purchased loans with credit deterioration				(6,000)
Impact of CECL adoption | Commercial real estate loans
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				7,730,000
Impact of CECL adoption - purchased loans with credit deterioration				333,000
Impact of CECL adoption | Commercial loans
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				(3,532,000)
Impact of CECL adoption - purchased loans with credit deterioration				(22,000)
Impact of CECL adoption | Municipal loans
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				(522,000)
Impact of CECL adoption - purchased loans with credit deterioration				0
Impact of CECL adoption | Loans to individuals
Allowance for Loan Losses [Roll Forward]
Impact of CECL adoption - cumulative effect adjustment				(125,000)
Impact of CECL adoption - purchased loans with credit deterioration				$ (59,000)
[1] The increase in the provision for credit losses during 2020 was primarily due to the economic impact of COVID-19 on macroeconomic factors used in the CECL methodology.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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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 credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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