Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 36,303	$ 35,449	$ 36,515	$ 35,273
Loans charged-off	(1,262)	(686)	(2,632)	(1,720)
Recoveries of loans charged-off	378	449	1,170	1,505
Net loans (charged-off) recovered	(884)	(237)	(1,462)	(215)
Provision for (reversal of) loan losses	6,341	1,294	6,707	1,448
Balance at end of period	41,760	36,506	41,760	36,506
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	3,395	3,399	3,164	3,787
Loans charged-off	0	0	(63)	0
Recoveries of loans charged-off	0	0	1	1
Net loans (charged-off) recovered	0	0	(62)	1
Provision for (reversal of) loan losses	1,019	136	1,312	(253)
Balance at end of period	4,414	3,535	4,414	3,535
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,660	2,024	2,173	1,866
Loans charged-off	0	(66)	(71)	(66)
Recoveries of loans charged-off	62	4	108	96
Net loans (charged-off) recovered	62	(62)	37	30
Provision for (reversal of) loan losses	17	44	529	110
Balance at end of period	2,739	2,006	2,739	2,006
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	28,012	27,221	28,701	26,980
Loans charged-off	0	0	0	0
Recoveries of loans charged-off	0	0	1	81
Net loans (charged-off) recovered	0	0	1	81
Provision for (reversal of) loan losses	4,327	1,273	3,637	1,433
Balance at end of period	32,339	28,494	32,339	28,494
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,017	2,558	2,235	2,397
Loans charged-off	(744)	(192)	(1,113)	(369)
Recoveries of loans charged-off	65	139	268	469
Net loans (charged-off) recovered	(679)	(53)	(845)	100
Provision for (reversal of) loan losses	731	(272)	679	(264)
Balance at end of period	2,069	2,233	2,069	2,233
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	37	46	45	47
Loans charged-off	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	(17)	(2)	(25)	(3)
Balance at end of period	20	44	20	44
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	182	201	197	196
Loans charged-off	(518)	(428)	(1,385)	(1,285)
Recoveries of loans charged-off	251	306	792	858
Net loans (charged-off) recovered	(267)	(122)	(593)	(427)
Provision for (reversal of) loan losses	264	115	575	425
Balance at end of period	$ 179	$ 194	$ 179	$ 194

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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- 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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- 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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