Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 15,852	$ 15,287	$ 15,523	$ 14,855
Provision for loan losses	400	500	900	1,000
Loan charge-offs	(311)	(373)	(604)	(563)
Loan recoveries	159	30	281	152
Net loan charge-offs	(152)	(343)	(323)	(441)
Balance, end of period	$ 16,100	$ 15,444	$ 16,100	$ 15,444
Net charge-offs to average loans (annualized)	0.04%	0.11%	0.04%	0.03%
Allowance for loan losses to gross loans	1.05%	1.19%
Allowance for loan losses to nonperforming loans	208.52%	293.75%
Commercial [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period			$ 9,937
Balance, end of period	$ 10,673		10,673
Commercial [Member] \| Owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	2,680	$ 3,052	2,534	$ 2,843
Provision for loan losses	19	(88)	165	121
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	2,699	2,964	2,699	2,964
Commercial [Member] \| Non-owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,366	2,967	3,230	2,778
Provision for loan losses	342	255	478	623
Loan charge-offs	(234)	(253)	(234)	(433)
Loan recoveries	107	12	107	13
Net loan charge-offs	(127)	(241)	(127)	(420)
Balance, end of period	3,581	2,981	3,581	2,981
Commercial [Member] \| Business [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,553	3,823	3,848	4,123
Provision for loan losses	280	139	(14)	(182)
Loan charge-offs		(120)	(119)	(130)
Loan recoveries	16	15	134	46
Net loan charge-offs	16	(105)	15	(84)
Balance, end of period	3,849	3,857	3,849	3,857
Commercial [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	415	334	325	295
Provision for loan losses	129	16	219	55
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	544	350	544	350
Consumer [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period			5,586
Balance, end of period	5,427		5,427
Consumer [Member] \| Other [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	280	373	281	309
Provision for loan losses	(12)	(78)	19	(14)
Loan charge-offs			(34)
Loan recoveries			2
Net loan charge-offs			(32)
Balance, end of period	268	295	268	295
Consumer [Member] \| Real Estate [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,391	2,830	3,495	2,780
Provision for loan losses	54	240	25	200
Loan charge-offs			(77)
Loan recoveries	1	(9)	3	81
Net loan charge-offs	1	(9)	(74)	81
Balance, end of period	3,446	3,061	3,446	3,061
Consumer [Member] \| Home equity [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	1,911	1,619	1,600	1,475
Provision for loan losses	(438)	(23)	(64)	121
Loan charge-offs	(77)		(140)
Loan recoveries	35	12	35	12
Net loan charge-offs	(42)	12	(105)	12
Balance, end of period	1,431	1,608	1,431	1,608
Consumer [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	256	289	210	252
Provision for loan losses	26	39	72	76
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	$ 282	$ 328	$ 282	$ 328

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.

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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.

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from recovery of amount previously written off or reestablishment of reserve previously utilized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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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