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Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 42,674	$ 36,515	$ 36,515
Loans charged-off	(634)	(633)	(4,204)
Recoveries of loans charged-off	347	362
Net loans (charged-off) recovered	(287)	(271)
Provision for (reversal of) loan losses	1,170	88
Balance at end of period	43,557	36,332	42,674
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	5,287	3,164	3,164
Loans charged-off	0	0	(92)
Recoveries of loans charged-off	0	1
Net loans (charged-off) recovered	0	1
Provision for (reversal of) loan losses	(367)	(13)
Balance at end of period	4,920	3,152	5,287
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,840	2,173	2,173
Loans charged-off	(22)	(49)	(119)
Recoveries of loans charged-off	11	5
Net loans (charged-off) recovered	(11)	(44)
Provision for (reversal of) loan losses	(61)	185
Balance at end of period	2,768	2,314	2,840
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	32,266	28,701	28,701
Loans charged-off	0	0	(788)
Recoveries of loans charged-off	3	0
Net loans (charged-off) recovered	3	0
Provision for (reversal of) loan losses	624	20
Balance at end of period	32,893	28,721	32,266
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,086	2,235	2,235
Loans charged-off	(151)	(109)	(1,283)
Recoveries of loans charged-off	56	60
Net loans (charged-off) recovered	(95)	(49)
Provision for (reversal of) loan losses	783	(285)
Balance at end of period	2,774	1,901	2,086
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	19	45	45
Loans charged-off	0	0	0
Recoveries of loans charged-off	0	0
Net loans (charged-off) recovered	0	0
Provision for (reversal of) loan losses	0	(1)
Balance at end of period	19	44	19
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	176	197	197
Loans charged-off	(461)	(475)	(1,922)
Recoveries of loans charged-off	277	296
Net loans (charged-off) recovered	(184)	(179)
Provision for (reversal of) loan losses	191	182
Balance at end of period	$ 183	$ 200	$ 176

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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