Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 15,523	$ 14,855
Provision for loan losses	500	500
Loan charge-offs	(293)	(190)
Loan recoveries	122	122
Net loan charge-offs	(171)	(68)
Balance, end of period	$ 15,852	$ 15,287
Net charge-offs to average loans (annualized)	0.05%	0.02%
Allowance for loan losses to gross loans	1.09%	1.25%
Allowance for loan losses to nonperforming loans	217.92%	247.43%
Commercial [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 9,937
Balance, end of period	10,014
Commercial [Member] \| Owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	2,534	$ 2,843
Provision for loan losses	146	209
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	2,680	3,052
Commercial [Member] \| Non-owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,230	2,778
Provision for loan losses	135	369
Loan charge-offs		(181)
Loan recoveries	1	1
Net loan charge-offs	1	(180)
Balance, end of period	3,366	2,967
Commercial [Member] \| Business [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,848	4,123
Provision for loan losses	(294)	(321)
Loan charge-offs	(119)	(9)
Loan recoveries	118	30
Net loan charge-offs	(1)	21
Balance, end of period	3,553	3,823
Commercial [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	325	295
Provision for loan losses	90	39
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	415	334
Consumer [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	5,586
Balance, end of period	5,838
Consumer [Member] \| Other [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	281	309
Provision for loan losses	31	64
Loan charge-offs	(34)
Loan recoveries	2
Net loan charge-offs	(32)
Balance, end of period	280	373
Consumer [Member] \| Real Estate [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,495	2,780
Provision for loan losses	(105)	(40)
Loan charge-offs
Loan recoveries	1	90
Net loan charge-offs	1	90
Balance, end of period	3,391	2,830
Consumer [Member] \| Home equity [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	1,600	1,475
Provision for loan losses	451	143
Loan charge-offs	(140)
Loan recoveries		1
Net loan charge-offs	(140)	1
Balance, end of period	1,911	1,619
Consumer [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	210	252
Provision for loan losses	46	37
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	$ 256	$ 289

Allowance for loan and lease losses write offs net of recoveries.

No definition available.

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- Definition

Allowance for loan losses as a percentage of gross loans.

+ References

No definition available.

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- Definition

Allowance for credit losses as a percentage of nonperforming loans.

+ References

No definition available.

+ Details

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- Definition

Net loan charge offs annualized as a percentage of average total loans.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from recoveries of amounts previously written off or reestablishment of reserves that had previously been utilized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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