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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses - Past due aging analysis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	$ 1,721,279	$ 1,701,850
Interest income foregone on nonaccrual loans	400	300	$ 200
Performing
Past due aging analysis of loans
Accruing Current	1,711,189	1,688,311
Nonperforming
Past due aging analysis of loans
Nonaccrual	7,379	6,963
30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	2,263	6,576
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	1,000,225	969,634
Commercial \| Performing
Past due aging analysis of loans
Accruing Current	992,858	961,724
Commercial \| Nonperforming
Past due aging analysis of loans
Nonaccrual	6,302	5,095
Commercial \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	1,065	2,815
Commercial \| Commercial and industrial
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	479,144	510,706
Commercial \| Commercial and industrial \| Performing
Past due aging analysis of loans
Accruing Current	473,900	504,313
Commercial \| Commercial and industrial \| Nonperforming
Past due aging analysis of loans
Nonaccrual	4,862	3,578
Commercial \| Commercial and industrial \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	382	2,815
Commercial \| Real estate construction
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	26,378	18,965
Commercial \| Real estate construction \| Performing
Past due aging analysis of loans
Accruing Current	26,251	18,965
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	494,703	439,963
Commercial \| Commercial real estate \| Performing
Past due aging analysis of loans
Accruing Current	492,707	438,446
Commercial \| Commercial real estate \| Nonperforming
Past due aging analysis of loans
Nonaccrual	1,440	1,517
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	721,054	732,216
Consumer \| Performing
Past due aging analysis of loans
Accruing Current	718,331	726,587
Consumer \| Nonperforming
Past due aging analysis of loans
Nonaccrual	1,077	1,868
Consumer \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	1,198	3,761
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	457,155	448,143
Consumer \| Residential \| Real estate first mortgage \| Performing
Past due aging analysis of loans
Accruing Current	455,244	444,470
Consumer \| Residential \| Real estate first mortgage \| Nonperforming
Past due aging analysis of loans
Nonaccrual	797	1,262
Consumer \| Residential \| Real estate first mortgage \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	666	2,411
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	177,373	188,855
Consumer \| Residential \| Real estate junior lien \| Performing
Past due aging analysis of loans
Accruing Current	176,915	187,502
Consumer \| Residential \| Real estate junior lien \| Nonperforming
Past due aging analysis of loans
Nonaccrual	274	584
Consumer \| Residential \| Real estate junior lien \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	184	769
Consumer \| Other revolving and installment
Past due aging analysis of loans
Loans and Leases Receivable, Gross, Total	86,526	95,218
Consumer \| Other revolving and installment \| Performing
Past due aging analysis of loans
Accruing Current	86,172	94,615
Consumer \| Other revolving and installment \| Nonperforming
Past due aging analysis of loans
Nonaccrual	6	22
Consumer \| Other revolving and installment \| 30 - 89 Days Past Due \| Performing
Past due aging analysis of loans
Past due	$ 348	$ 581