Loans and Allowance for Loan Losses (Details 7) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Summary of key information for impaired loans
Unpaid Principal Balance	$ 17,334	$ 15,542
Impaired loans	12,557	11,157
Impaired loans with related allowance for loan losses	9,350	7,492
Related allowance for loan losses	3,742	2,644
Commercial [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	14,574	13,221
Impaired loans	9,831	8,867
Impaired loans with related allowance for loan losses	6,624	5,472
Related allowance for loan losses	2,280	1,874
Commercial [Member] \| Owner occupied RE [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,232	2,284
Impaired loans	2,177	2,243
Impaired loans with related allowance for loan losses	830	2,224
Related allowance for loan losses	192	263
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	7,854	7,238
Impaired loans	4,299	4,031
Impaired loans with related allowance for loan losses	3,704	1,638
Related allowance for loan losses	948	457
Commercial [Member] \| Construction [Member]
Summary of key information for impaired loans
Unpaid Principal Balance
Impaired loans
Impaired loans with related allowance for loan losses
Related allowance for loan losses
Commercial [Member] \| Business [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	4,488	3,699
Impaired loans	3,355	2,593
Impaired loans with related allowance for loan losses	2,090	1,610
Related allowance for loan losses	1,140	1,154
Consumer [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,760	2,321
Impaired loans	2,726	2,290
Impaired loans with related allowance for loan losses	2,726	2,020
Related allowance for loan losses	1,462	770
Consumer [Member] \| Real estate [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,382	1,853
Impaired loans	2,357	1,843
Impaired loans with related allowance for loan losses	2,357	1,843
Related allowance for loan losses	1,304	682
Consumer [Member] \| Home equity [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	203	207
Impaired loans	195	257
Impaired loans with related allowance for loan losses	195
Related allowance for loan losses	133
Consumer [Member] \| Construction [Member]
Summary of key information for impaired loans
Unpaid Principal Balance
Impaired loans
Impaired loans with related allowance for loan losses
Related allowance for loan losses
Consumer [Member] \| Other [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	175	261
Impaired loans	174	190
Impaired loans with related allowance for loan losses	174	177
Related allowance for loan losses	$ 25	$ 88

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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