Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses Allowance for Loan and Lease Losses 2 (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	$ 15,738	$ 16,029
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	4,711	4,396
Allowance for loan and lease losses	20,449	20,425	$ 18,638	$ 18,763
Financing Receivable, Collectively Evaluated for Impairment	1,633,937	1,593,576
Financing Receivable, Individually Evaluated for Impairment	23,560	25,308
Loans and Leases Receivable, Gross	1,657,646	1,619,057
Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Financing Receivable, Individually Evaluated for Impairment	149	173
Commercial real estate:
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	10,515	10,987
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	690	675
Allowance for loan and lease losses	11,205	11,662	9,990	10,131
Financing Receivable, Collectively Evaluated for Impairment	1,119,386	1,086,254
Financing Receivable, Individually Evaluated for Impairment	7,368	7,914
Loans and Leases Receivable, Gross	1,126,901	1,094,339
Commercial real estate: \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Financing Receivable, Individually Evaluated for Impairment	147	171
Commercial and industrial loans and leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,501	4,369
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	3,984	3,710
Allowance for loan and lease losses	8,485	8,079	8,151	8,225
Financing Receivable, Collectively Evaluated for Impairment	483,109	478,385
Financing Receivable, Individually Evaluated for Impairment	15,890	17,104
Loans and Leases Receivable, Gross	499,001	495,491
Commercial and industrial loans and leases \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Financing Receivable, Individually Evaluated for Impairment	2	2
Consumer and other:
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	722	673
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	37	11
Allowance for loan and lease losses	759	684	$ 497	$ 407
Financing Receivable, Collectively Evaluated for Impairment	31,442	28,937
Financing Receivable, Individually Evaluated for Impairment	302	290
Loans and Leases Receivable, Gross	31,744	29,227
Consumer and other: \| Loans acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Financing Receivable, Individually Evaluated for Impairment	$ 0	$ 0

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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