Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 35,524	$ 41,454	$ 35,273	$ 49,006
Loans charged-off	479	527	1,034	1,322
Recoveries of loans charged-off	516	466	1,056	1,088
Net loans (charged-off) recovered	(37)	61	(22)	234
Net loans (charged-off) recovered	(112)	1,520	154	(5,859)
Balance at end of period	35,449	42,913	35,449	42,913
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	3,604	8,201	3,787	6,490
Loans charged-off	0	0	0	0
Recoveries of loans charged-off	1	0	1	1
Net loans (charged-off) recovered	(1)	0	(1)	(1)
Net loans (charged-off) recovered	(206)	(183)	(389)	1,527
Balance at end of period	3,399	8,018	3,399	8,018
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	1,982	2,508	1,866	2,270
Loans charged-off	0	28	0	101
Recoveries of loans charged-off	53	12	92	67
Net loans (charged-off) recovered	(53)	16	(92)	34
Net loans (charged-off) recovered	(11)	28	66	284
Balance at end of period	2,024	2,520	2,024	2,520
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	27,225	27,236	26,980	35,709
Loans charged-off	0	0	0	0
Recoveries of loans charged-off	34	1	81	1
Net loans (charged-off) recovered	(34)	(1)	(81)	(1)
Net loans (charged-off) recovered	(38)	1,693	160	(6,780)
Balance at end of period	27,221	28,930	27,221	28,930
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,454	3,108	2,397	4,107
Loans charged-off	46	116	177	435
Recoveries of loans charged-off	114	179	330	461
Net loans (charged-off) recovered	(68)	(63)	(153)	(26)
Net loans (charged-off) recovered	36	(74)	8	(1,036)
Balance at end of period	2,558	3,097	2,558	3,097
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	48	46	47	46
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
Net loans (charged-off) recovered	(2)	1	(1)	1
Balance at end of period	46	47	46	47
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	211	355	196	384
Loans charged-off	433	383	857	786
Recoveries of loans charged-off	314	274	552	558
Net loans (charged-off) recovered	119	109	305	228
Net loans (charged-off) recovered	109	55	310	145
Balance at end of period	$ 201	$ 301	$ 201	$ 301

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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