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Loans and Allowance for Credit Losses - Amortized Cost and Unpaid Principal of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	$ 2,400,627		$ 2,295,499
Allowance for credit losses	(33,293)	$ (25,461)	(23,737)	$ (23,357)	$ (22,585)	$ (22,020)
Net loans	2,367,334		2,271,762
Unpaid Principal	2,410,593		2,305,663
Difference	(9,966)		(10,164)
Commercial & industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	480,606		450,826
Allowance for credit losses	(14,754)	(6,228)	(6,707)	(7,512)	(7,508)	(5,800)
Unpaid Principal	482,685		453,153
Difference	(2,079)		(2,327)
Commercial real estate: \| Owner occupied properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	455,883		433,157
Allowance for credit losses	(2,654)	(2,623)	(2,207)	(2,393)	(2,271)	(2,944)
Unpaid Principal	457,827		435,050
Difference	(1,944)		(1,893)
Commercial real estate: \| Non-owner occupied and multifamily properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	826,579		763,180
Allowance for credit losses	(5,640)	(5,108)	(4,440)	(4,362)	(4,183)	(3,967)
Unpaid Principal	831,170		767,617
Difference	(4,591)		(4,437)
Residential real estate: \| 1-4 family residential properties secured by first liens
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	239,968		243,185
Allowance for credit losses	(5,920)	(6,497)	(5,712)	(4,964)	(4,693)	(4,364)
Unpaid Principal	240,018		243,167
Difference	(50)		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	86,426		67,116
Allowance for credit losses	(1,370)	(1,308)	(1,041)	(1,009)	(928)	(775)
Unpaid Principal	85,450		66,470
Difference	976		646
Residential real estate: \| 1-4 family residential construction loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	32,354		39,059
Allowance for credit losses	(192)	(159)	(324)	(282)	(270)	(230)
Unpaid Principal	32,539		39,311
Difference	(185)		(252)
Other construction, land development and raw land loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	126,858		173,589
Allowance for credit losses	(2,106)	(2,848)	(2,839)	(2,421)	(2,308)	(3,589)
Unpaid Principal	128,484		175,261
Difference	(1,626)		(1,672)
Obligations of states and political subdivisions in the US
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	16,784		32,434
Allowance for credit losses	(77)	(184)	(143)	(132)	(135)	(106)
Unpaid Principal	16,949		32,433
Difference	(165)		1
Agricultural production, including commercial fishing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	58,981		47,445
Allowance for credit losses	(252)	(240)	(202)	(189)	(197)	(169)
Unpaid Principal	59,259		47,682
Difference	(278)		(237)
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	12,018		9,763
Allowance for credit losses	(149)	(122)	(114)	(87)	(82)	(71)
Unpaid Principal	11,887		9,659
Difference	131		104
Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost	64,170		35,745
Allowance for credit losses	(179)	$ (144)	(8)	$ (6)	$ (10)	$ (5)
Unpaid Principal	64,325		35,860
Difference	$ (155)		$ (115)