Loans, net and allowance for credit losses- Major Classification of Loans by Past Due Status (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	$ 4,302,821	$ 4,066,896
Loans > 90 Days and Accruing	451	524
Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	19,780	23,903
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	7,690	11,241
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,407	4,266
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	7,683	8,396
Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,283,041	4,042,993
Commercial and industrial
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	712,705	667,948
Commercial and industrial \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,752	3,064
Commercial and industrial \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	422	1,090
Commercial and industrial \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	403	147
Commercial and industrial \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	927	1,827
Commercial and industrial \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	710,953	664,884
Municipal
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	200,552	202,303
Municipal \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	200,552	202,303
Real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,130,510	2,916,419
Commercial real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,490,510	2,314,110
Commercial real estate \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	9,427	8,952
Commercial real estate \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,641	3,943
Commercial real estate \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,028	1,459
Commercial real estate \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,758	3,550
Commercial real estate \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,481,083	2,305,158
Residential real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	640,000	602,309
Loans > 90 Days and Accruing	451	524
Loans in the formal process of foreclosure	0	600
Residential real estate \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,878	6,109
Residential real estate \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,954	2,948
Residential real estate \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	426	1,413
Residential real estate \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,498	1,748
Residential real estate \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	635,122	596,200
Consumer
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	99,496	111,238
Consumer \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,242	3,803
Consumer \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,701	2,527
Consumer \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	359	500
Consumer \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	182	776
Consumer \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	97,254	107,435
Equipment financing
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	159,558	168,988
Equipment financing \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,481	1,975
Equipment financing \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	972	733
Equipment financing \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	191	747
Equipment financing \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	318	495
Equipment financing \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	$ 158,077	$ 167,013

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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