Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 43,557	$ 36,332	$ 42,674	$ 36,515	$ 36,515
Loans charged-off	(721)	(737)	(1,355)	(1,370)	(4,204)
Recoveries of loans charged-off	444	430	791	792
Net loans (charged-off) recovered	(277)	(307)	(564)	(578)
Provision for (reversal of) loan losses	(873)	278	297	366
Balance at end of period	42,407	36,303	42,407	36,303	42,674
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	4,920	3,152	5,287	3,164	3,164
Loans charged-off	(24)	(63)	(24)	(63)	(92)
Recoveries of loans charged-off	0	0	0	1
Net loans (charged-off) recovered	(24)	(63)	(24)	(62)
Provision for (reversal of) loan losses	(162)	306	(529)	293
Balance at end of period	4,734	3,395	4,734	3,395	5,287
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,768	2,314	2,840	2,173	2,173
Loans charged-off	(106)	(22)	(128)	(71)	(119)
Recoveries of loans charged-off	33	41	44	46
Net loans (charged-off) recovered	(73)	19	(84)	(25)
Provision for (reversal of) loan losses	9	327	(52)	512
Balance at end of period	2,704	2,660	2,704	2,660	2,840
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	32,893	28,721	32,266	28,701	28,701
Loans charged-off	0	0	0	0	(788)
Recoveries of loans charged-off	0	1	3	1
Net loans (charged-off) recovered	0	1	3	1
Provision for (reversal of) loan losses	(1,052)	(710)	(428)	(690)
Balance at end of period	31,841	28,012	31,841	28,012	32,266
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,774	1,901	2,086	2,235	2,235
Loans charged-off	(216)	(260)	(367)	(369)	(1,283)
Recoveries of loans charged-off	191	143	247	203
Net loans (charged-off) recovered	(25)	(117)	(120)	(166)
Provision for (reversal of) loan losses	193	233	976	(52)
Balance at end of period	2,942	2,017	2,942	2,017	2,086
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	19	44	19	45	45
Loans charged-off	0	0	0	0	0
Recoveries of loans charged-off	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Provision for (reversal of) loan losses	(1)	(7)	(1)	(8)
Balance at end of period	18	37	18	37	19
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	183	200	176	197	197
Loans charged-off	(375)	(392)	(836)	(867)	(1,922)
Recoveries of loans charged-off	220	245	497	541
Net loans (charged-off) recovered	(155)	(147)	(339)	(326)
Provision for (reversal of) loan losses	140	129	331	311
Balance at end of period	$ 168	$ 182	$ 168	$ 182	$ 176

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

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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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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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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.

+ 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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