Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 44,421	$ 42,407	$ 44,884	$ 42,674	$ 42,674
Loans charged-off	(1,335)	(773)	(3,142)	(2,128)	(3,360)
Recoveries of loans charged-off	491	365	1,143	1,156
Net loans (charged-off) recovered	(844)	(408)	(1,999)	(972)
Provision for (reversal of) loan losses	1,717	2,277	2,409	2,574
Balance at end of period	45,294	44,276	45,294	44,276	44,884
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	6,194	4,734	3,958	5,287	5,287
Loans charged-off	0	0	0	(24)	(24)
Recoveries of loans charged-off	0	0	0	0
Net loans (charged-off) recovered	0	0	0	(24)
Provision for (reversal of) loan losses	30	421	2,266	(108)
Balance at end of period	6,224	5,155	6,224	5,155	3,958
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,781	2,704	2,780	2,840	2,840
Loans charged-off	0	(133)	(69)	(261)	(261)
Recoveries of loans charged-off	9	47	24	91
Net loans (charged-off) recovered	9	(86)	(45)	(170)
Provision for (reversal of) loan losses	38	172	93	120
Balance at end of period	2,828	2,790	2,828	2,790	2,780
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	30,701	31,841	35,526	32,266	32,266
Loans charged-off	0	0	0	0	(78)
Recoveries of loans charged-off	4	1	13	4
Net loans (charged-off) recovered	4	1	13	4
Provision for (reversal of) loan losses	383	1,917	(4,451)	1,489
Balance at end of period	31,088	33,759	31,088	33,759	35,526
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	4,433	2,942	2,448	2,086	2,086
Loans charged-off	(833)	(127)	(1,716)	(494)	(1,173)
Recoveries of loans charged-off	255	92	520	339
Net loans (charged-off) recovered	(578)	(35)	(1,196)	(155)
Provision for (reversal of) loan losses	945	(507)	3,548	469
Balance at end of period	4,800	2,400	4,800	2,400	2,448
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	14	18	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	(1)	(3)	(3)	(4)
Balance at end of period	13	15	13	15	16
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	298	168	156	176	176
Loans charged-off	(502)	(513)	(1,357)	(1,349)	(1,824)
Recoveries of loans charged-off	223	225	586	722
Net loans (charged-off) recovered	(279)	(288)	(771)	(627)
Provision for (reversal of) loan losses	322	277	956	608
Balance at end of period	$ 341	$ 157	$ 341	$ 157	$ 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
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-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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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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