Loans and Allowance for Loan Losses - Past due aging analysis (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	$ 2,034,197	$ 1,721,279
Performing
Past due aging analysis of loans
Accruing Current	2,025,699	1,711,189
Nonaccrual	5,328	7,379
Loans and Leases Receivable, Gross, Total	2,034,197	1,721,279
30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	3,170	2,263
90 Days or More Past Due \| Performing
Past due aging analysis of loans
Past due		448
Commercial
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	1,344,652	1,000,225
Commercial \| Performing
Past due aging analysis of loans
Accruing Current	1,339,676	992,858
Nonaccrual	4,314	6,302
Loans and Leases Receivable, Gross, Total	1,344,652	1,000,225
Commercial \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	662	1,065
Commercial \| Commercial and industrial
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	794,204	479,144
Commercial \| Commercial and industrial \| Performing
Past due aging analysis of loans
Accruing Current	790,675	473,900
Nonaccrual	2,867	4,862
Loans and Leases Receivable, Gross, Total	794,204	479,144
Commercial \| Commercial and industrial \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	662	382
Commercial \| Real estate construction
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	31,344	26,378
Commercial \| Real estate construction \| Performing
Past due aging analysis of loans
Accruing Current	31,344	26,251
Loans and Leases Receivable, Gross, Total	31,344	26,378
Commercial \| Real estate construction \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due		127
Commercial \| Commercial real estate
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	519,104	494,703
Commercial \| Commercial real estate \| Performing
Past due aging analysis of loans
Accruing Current	517,657	492,707
Nonaccrual	1,447	1,440
Loans and Leases Receivable, Gross, Total	519,104	494,703
Commercial \| Commercial real estate \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due		556
Consumer
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	689,545	721,054
Consumer \| Performing
Past due aging analysis of loans
Accruing Current	686,023	718,331
Nonaccrual	1,014	1,077
Loans and Leases Receivable, Gross, Total	689,545	721,054
Consumer \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	2,508	1,198
Consumer \| 90 Days or More Past Due \| Performing
Past due aging analysis of loans
Past due		448
Consumer \| Residential \| Real estate first mortgage
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	456,737	457,155
Consumer \| Residential \| Real estate first mortgage \| Performing
Past due aging analysis of loans
Accruing Current	453,810	455,244
Nonaccrual	764	797
Loans and Leases Receivable, Gross, Total	456,737	457,155
Consumer \| Residential \| Real estate first mortgage \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	2,163	666
Consumer \| Residential \| Real estate first mortgage \| 90 Days or More Past Due \| Performing
Past due aging analysis of loans
Past due		448
Consumer \| Residential \| Real estate junior lien
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	154,351	177,373
Consumer \| Residential \| Real estate junior lien \| Performing
Past due aging analysis of loans
Accruing Current	153,907	176,915
Nonaccrual	211	274
Loans and Leases Receivable, Gross, Total	154,351	177,373
Consumer \| Residential \| Real estate junior lien \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	233	184
Consumer \| Other revolving and installment
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	78,457	86,526
Consumer \| Other revolving and installment \| Performing
Past due aging analysis of loans
Accruing Current	78,306	86,172
Nonaccrual	39	6
Loans and Leases Receivable, Gross, Total	78,457	86,526
Consumer \| Other revolving and installment \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	$ 112	$ 348

Amount of financing receivable not past due.

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Amount of financing receivable on nonaccrual status.

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