Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 36,515	$ 35,273
Loans charged-off	(633)	(555)
Recoveries of loans charged-off	362	540
Net loans (charged-off) recovered	(271)	(15)
Provision for (reversal of) loan losses	88	266
Balance at end of period	36,332	35,524
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	3,164	3,787
Loans charged-off	0	0
Recoveries of loans charged-off	1	0
Net loans (charged-off) recovered	1	0
Provision for (reversal of) loan losses	(13)	(183)
Balance at end of period	3,152	3,604
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,173	1,866
Loans charged-off	(49)	0
Recoveries of loans charged-off	5	39
Net loans (charged-off) recovered	(44)	39
Provision for (reversal of) loan losses	185	77
Balance at end of period	2,314	1,982
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	28,701	26,980
Loans charged-off	0	0
Recoveries of loans charged-off	0	47
Net loans (charged-off) recovered	0	47
Provision for (reversal of) loan losses	20	198
Balance at end of period	28,721	27,225
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,235	2,397
Loans charged-off	(109)	(131)
Recoveries of loans charged-off	60	216
Net loans (charged-off) recovered	(49)	85
Provision for (reversal of) loan losses	(285)	(28)
Balance at end of period	1,901	2,454
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	45	47
Loans charged-off	0	0
Recoveries of loans charged-off	0	0
Net loans (charged-off) recovered	0	0
Provision for (reversal of) loan losses	(1)	1
Balance at end of period	44	48
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	197	196
Loans charged-off	(475)	(424)
Recoveries of loans charged-off	296	238
Net loans (charged-off) recovered	(179)	(186)
Provision for (reversal of) loan losses	182	201
Balance at end of period	$ 200	$ 211

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

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

+ References

No definition available.

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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