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, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 44,623	$ 43,557	$ 44,884	$ 42,674	$ 42,674
Loans charged-off	(1,194)	(721)	(1,807)	(1,355)	(3,360)
Recoveries of loans charged-off	342	444	652	791
Net loans (charged-off) recovered	(852)	(277)	(1,155)	(564)
Provision for (reversal of) loan losses	650	(873)	692	297
Balance at end of period	44,421	42,407	44,421	42,407	44,884
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	3,887	4,920	3,958	5,287	5,287
Loans charged-off	0	(24)	0	(24)	(24)
Recoveries of loans charged-off	0	0	0	0
Net loans (charged-off) recovered	0	(24)	0	(24)
Provision for (reversal of) loan losses	2,307	(162)	2,236	(529)
Balance at end of period	6,194	4,734	6,194	4,734	3,958
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,709	2,768	2,780	2,840	2,840
Loans charged-off	(56)	(106)	(69)	(128)	(261)
Recoveries of loans charged-off	7	33	15	44
Net loans (charged-off) recovered	(49)	(73)	(54)	(84)
Provision for (reversal of) loan losses	121	9	55	(52)
Balance at end of period	2,781	2,704	2,781	2,704	2,780
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	34,730	32,893	35,526	32,266	32,266
Loans charged-off	0	0	0	0	(78)
Recoveries of loans charged-off	4	0	9	3
Net loans (charged-off) recovered	4	0	9	3
Provision for (reversal of) loan losses	(4,033)	(1,052)	(4,834)	(428)
Balance at end of period	30,701	31,841	30,701	31,841	35,526
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	3,128	2,774	2,448	2,086	2,086
Loans charged-off	(727)	(216)	(883)	(367)	(1,173)
Recoveries of loans charged-off	163	191	265	247
Net loans (charged-off) recovered	(564)	(25)	(618)	(120)
Provision for (reversal of) loan losses	1,869	193	2,603	976
Balance at end of period	4,433	2,942	4,433	2,942	2,448
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	14	19	16	19	19
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	0	(1)	(2)	(1)
Balance at end of period	14	18	14	18	16
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	155	183	156	176	176
Loans charged-off	(411)	(375)	(855)	(836)	(1,824)
Recoveries of loans charged-off	168	220	363	497
Net loans (charged-off) recovered	(243)	(155)	(492)	(339)
Provision for (reversal of) loan losses	386	140	634	331
Balance at end of period	$ 298	$ 168	$ 298	$ 168	$ 156

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 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: 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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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
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