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, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 42,407	$ 36,303	$ 42,674	$ 36,515	$ 36,515
Loans charged-off	(773)	(1,262)	(2,128)	(2,632)	(4,204)
Recoveries of loans charged-off	365	378	1,156	1,170
Net loans (charged-off) recovered	(408)	(884)	(972)	(1,462)
Provision for (reversal of) loan losses	2,277	6,341	2,574	6,707
Balance at end of period	44,276	41,760	44,276	41,760	42,674
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	4,734	3,395	5,287	3,164	3,164
Loans charged-off	0	0	(24)	(63)	(92)
Recoveries of loans charged-off	0	0	0	1
Net loans (charged-off) recovered	0	0	(24)	(62)
Provision for (reversal of) loan losses	421	1,019	(108)	1,312
Balance at end of period	5,155	4,414	5,155	4,414	5,287
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,704	2,660	2,840	2,173	2,173
Loans charged-off	(133)	0	(261)	(71)	(119)
Recoveries of loans charged-off	47	62	91	108
Net loans (charged-off) recovered	(86)	62	(170)	37
Provision for (reversal of) loan losses	172	17	120	529
Balance at end of period	2,790	2,739	2,790	2,739	2,840
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	31,841	28,012	32,266	28,701	28,701
Loans charged-off	0	0	0	0	(788)
Recoveries of loans charged-off	1	0	4	1
Net loans (charged-off) recovered	1	0	4	1
Provision for (reversal of) loan losses	1,917	4,327	1,489	3,637
Balance at end of period	33,759	32,339	33,759	32,339	32,266
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,942	2,017	2,086	2,235	2,235
Loans charged-off	(127)	(744)	(494)	(1,113)	(1,283)
Recoveries of loans charged-off	92	65	339	268
Net loans (charged-off) recovered	(35)	(679)	(155)	(845)
Provision for (reversal of) loan losses	(507)	731	469	679
Balance at end of period	2,400	2,069	2,400	2,069	2,086
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	18	37	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	(3)	(17)	(4)	(25)
Balance at end of period	15	20	15	20	19
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	168	182	176	197	197
Loans charged-off	(513)	(518)	(1,349)	(1,385)	(1,922)
Recoveries of loans charged-off	225	251	722	792
Net loans (charged-off) recovered	(288)	(267)	(627)	(593)
Provision for (reversal of) loan losses	277	264	608	575
Balance at end of period	$ 157	$ 179	$ 157	$ 179	$ 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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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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