Loans, net and allowance for credit losses- Major Classification of Loans by Past Due Status (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	$ 4,190,202	$ 4,066,896
Loans > 90 Days and Accruing	160	524
Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	21,980	23,903
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	9,798	11,241
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,313	4,266
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	8,869	8,396
Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,168,092	4,042,993
Commercial and industrial
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	675,446	667,948
Loans > 90 Days and Accruing	130
Commercial and industrial \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,410	3,064
Commercial and industrial \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,200	1,090
Commercial and industrial \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	274	147
Commercial and industrial \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,936	1,827
Commercial and industrial \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	671,906	664,884
Municipal
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	212,586	202,303
Municipal \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	212,586	202,303
Real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,041,183	2,916,419
Commercial real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,423,027	2,314,110
Commercial real estate \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	8,507	8,952
Commercial real estate \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,190	3,943
Commercial real estate \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,415	1,459
Commercial real estate \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	4,902	3,550
Commercial real estate \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,414,520	2,305,158
Residential real estate
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	618,156	602,309
Loans > 90 Days and Accruing	1	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	5,564	6,109
Residential real estate \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	3,427	2,948
Residential real estate \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	946	1,413
Residential real estate \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,191	1,748
Residential real estate \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	612,592	596,200
Consumer
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	101,318	111,238
Loans > 90 Days and Accruing	29
Consumer \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,849	3,803
Consumer \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	2,107	2,527
Consumer \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	475	500
Consumer \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	267	776
Consumer \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	98,469	107,435
Equipment financing
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	159,669	168,988
Equipment financing \| Financial Assets, Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	1,650	1,975
Equipment financing \| 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	874	733
Equipment financing \| 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	203	747
Equipment financing \| Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	573	495
Equipment financing \| Current
Financing Receivable, Recorded Investment, Past Due.
Loans held for investment	$ 158,019	$ 167,013

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

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