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Loans and Allowance for Credit Losses - Amortized Cost and Unpaid Principal of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 2,386,328		$ 2,295,499
Allowance for credit losses	(25,461)	$ (24,812)	(23,737)	$ (22,585)	$ (20,922)	$ (22,020)
Net loans	2,360,867		2,271,762
Unpaid Principal	2,396,240		2,305,663
Difference	(9,912)		(10,164)
Commercial & industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	471,215		450,826
Allowance for credit losses	(6,228)	(6,371)	(6,707)	(7,508)	(7,387)	(5,800)
Unpaid Principal	473,342		453,153
Difference	(2,127)		(2,327)
Commercial real estate: \| Owner occupied properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	443,054		433,157
Allowance for credit losses	(2,623)	(2,498)	(2,207)	(2,271)	(2,442)	(2,944)
Unpaid Principal	444,880		435,050
Difference	(1,826)		(1,893)
Commercial real estate: \| Non-owner occupied and multifamily properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	769,928		763,180
Allowance for credit losses	(5,108)	(5,252)	(4,440)	(4,183)	(3,956)	(3,967)
Unpaid Principal	774,340		767,617
Difference	(4,412)		(4,437)
Residential real estate: \| 1-4 family residential properties secured by first liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	260,301		243,185
Allowance for credit losses	(6,497)	(6,220)	(5,712)	(4,693)	(4,056)	(4,364)
Unpaid Principal	260,371		243,167
Difference	(70)		18
Residential real estate: \| 1-4 family residential properties secured by junior liens and revolving secured by 1-4 family first liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	79,995		67,116
Allowance for credit losses	(1,308)	(1,083)	(1,041)	(928)	(769)	(775)
Unpaid Principal	79,125		66,470
Difference	870		646
Residential real estate: \| 1-4 family residential construction loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	28,839		39,059
Allowance for credit losses	(159)	(187)	(324)	(270)	(219)	(230)
Unpaid Principal	29,053		39,311
Difference	(214)		(252)
Other construction, land development and raw land loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	175,656		173,589
Allowance for credit losses	(2,848)	(2,615)	(2,839)	(2,308)	(1,706)	(3,589)
Unpaid Principal	177,280		175,261
Difference	(1,624)		(1,672)
Obligations of states and political subdivisions in the US
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	39,525		32,434
Allowance for credit losses	(184)	(140)	(143)	(135)	(123)	(106)
Unpaid Principal	39,692		32,433
Difference	(167)		1
Agricultural production, including commercial fishing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	55,833		47,445
Allowance for credit losses	(240)	(212)	(202)	(197)	(187)	(169)
Unpaid Principal	56,118		47,682
Difference	(285)		(237)
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	9,877		9,763
Allowance for credit losses	(122)	(102)	(114)	(82)	(71)	(71)
Unpaid Principal	9,758		9,659
Difference	119		104
Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	52,105		35,745
Allowance for credit losses	(144)	$ (132)	(8)	$ (10)	$ (6)	$ (5)
Unpaid Principal	52,281		35,860
Difference	$ (176)		$ (115)