Loans and Allowance for Loan Losses (Details 7) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary of key information for impaired loans
Unpaid Principal Balance	$ 17,086	$ 15,542
Impaired loans	12,446	11,157
Impaired loans with related allowance for loan losses	7,990	7,492
Related allowance for loan losses	3,677	2,644
Commercial [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	12,843	13,221
Impaired loans	8,664	8,867
Impaired loans with related allowance for loan losses	5,103	5,472
Related allowance for loan losses	1,990	1,874
Commercial [Member] \| Owner occupied RE [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,281	2,284
Impaired loans	2,235	2,243
Impaired loans with related allowance for loan losses	464	2,224
Related allowance for loan losses	179	263
Commercial [Member] \| Business [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	3,735	3,699
Impaired loans	2,764	2,593
Impaired loans with related allowance for loan losses	1,993	1,610
Related allowance for loan losses	1,061	1,154
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	6,827	7,238
Impaired loans	3,665	4,031
Impaired loans with related allowance for loan losses	2,646	1,638
Related allowance for loan losses	750	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
Consumer [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	4,243	2,321
Impaired loans	3,782	2,290
Impaired loans with related allowance for loan losses	2,887	2,020
Related allowance for loan losses	1,687	770
Consumer [Member] \| Other [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	171	261
Impaired loans	170	190
Impaired loans with related allowance for loan losses	170	177
Related allowance for loan losses	22	88
Consumer [Member] \| Real estate [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,062	1,853
Impaired loans	2,037	1,843
Impaired loans with related allowance for loan losses	2,037	1,843
Related allowance for loan losses	1,379	682
Consumer [Member] \| Home equity [Member]
Summary of key information for impaired loans
Unpaid Principal Balance	2,010	207
Impaired loans	1,575	257
Impaired loans with related allowance for loan losses	680
Related allowance for loan losses	286
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

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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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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

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