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, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	$ 45,595	$ 44,421	$ 45,100	$ 44,884	$ 44,884
Loans charged-off	(727)	(1,335)	(2,265)	(3,142)	(4,257)
Recoveries of loans charged-off	1,044	491	2,087	1,143
Net loans (charged-off) recovered	317	(844)	(178)	(1,999)
Provision for (reversal of) loan losses	946	1,717	1,936	2,409
Balance at end of period	46,858	45,294	46,858	45,294	45,100
Construction Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	6,521	6,194	7,951	3,958	3,958
Loans charged-off	0	0	0	0	(1)
Recoveries of loans charged-off	0	0	0	0
Net loans (charged-off) recovered	0	0	0	0
Provision for (reversal of) loan losses	536	30	(894)	2,266
Balance at end of period	7,057	6,224	7,057	6,224	7,951
1-4 Family Residential Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	2,812	2,781	2,830	2,780	2,780
Loans charged-off	(40)	0	(40)	(69)	(69)
Recoveries of loans charged-off	54	9	65	24
Net loans (charged-off) recovered	14	9	25	(45)
Provision for (reversal of) loan losses	62	38	33	93
Balance at end of period	2,888	2,828	2,888	2,828	2,830
Commercial Owner Occupied
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	5,867	5,417	5,655	5,603	5,603
Loans charged-off	0	0	0	0	0
Recoveries of loans charged-off	3	4	10	11
Net loans (charged-off) recovered	3	4	10	11
Provision for (reversal of) loan losses	(488)	185	(283)	(8)
Balance at end of period	5,382	5,606	5,382	5,606	5,655
Commercial Real Estate Loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	25,139	25,284	23,750	29,923	29,923
Loans charged-off	0	0	0	0	0
Recoveries of loans charged-off	0	0	0	2
Net loans (charged-off) recovered	0	0	0	2
Provision for (reversal of) loan losses	(538)	198	851	(4,443)
Balance at end of period	24,601	25,482	24,601	25,482	23,750
Commercial loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	5,115	4,433	4,588	2,448	2,448
Loans charged-off	(229)	(833)	(957)	(1,716)	(2,399)
Recoveries of loans charged-off	817	255	1,516	520
Net loans (charged-off) recovered	588	(578)	559	(1,196)
Provision for (reversal of) loan losses	1,073	945	1,629	3,548
Balance at end of period	6,776	4,800	6,776	4,800	4,588
Municipal loans
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	12	14	13	16	16
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	4	(1)	3	(3)
Balance at end of period	16	13	16	13	13
Loans to individuals
Allowances for Loan Losses [Roll Forward]
Balance at beginning of period	129	298	313	156	156
Loans charged-off	(458)	(502)	(1,268)	(1,357)	(1,788)
Recoveries of loans charged-off	170	223	496	586
Net loans (charged-off) recovered	(288)	(279)	(772)	(771)
Provision for (reversal of) loan losses	297	322	597	956
Balance at end of period	$ 138	$ 341	$ 138	$ 341	$ 313

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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