Loans and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 1,459,382	$ 1,387,070
Less-allowance for loan losses	(15,852)	(15,523)
Total loans, net	$ 1,443,530	$ 1,371,547
Total gross loans, net of deferred fees, (Percentage)	100.00%	100.00%
Commercial [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 969,705	$ 906,953
Total gross loans, net of deferred fees, (Percentage)	66.40%	65.40%
Commercial [Member] \| Owner occupied RE [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 339,444	$ 316,818
Total gross loans, net of deferred fees, (Percentage)	23.30%	22.80%
Commercial [Member] \| Non-owner occupied RE [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 339,231	$ 312,798
Total gross loans, net of deferred fees, (Percentage)	23.20%	22.60%
Commercial [Member] \| Business [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 234,820	$ 226,158
Total gross loans, net of deferred fees, (Percentage)	16.10%	16.30%
Commercial [Member] \| Construction [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 56,210	$ 51,179
Total gross loans, net of deferred fees, (Percentage)	3.80%	3.70%
Consumer [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 489,677	$ 480,117
Total gross loans, net of deferred fees, (Percentage)	33.60%	34.60%
Consumer [Member] \| Other [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 23,422	$ 22,575
Total gross loans, net of deferred fees, (Percentage)	1.60%	1.60%
Consumer [Member] \| Real estate [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 275,731	$ 273,050
Total gross loans, net of deferred fees, (Percentage)	18.90%	19.70%
Consumer [Member] \| Home equity [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 155,507	$ 156,141
Total gross loans, net of deferred fees, (Percentage)	10.70%	11.30%
Consumer [Member] \| Construction [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 35,017	$ 28,351
Total gross loans, net of deferred fees, (Percentage)	2.40%	2.00%

Loans and leases receivable net of deferred income percentage.

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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 and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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