Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 15,287	$ 13,898	$ 14,855	$ 13,629
Provision for loan losses	500	575	1,000	1,200
Loan charge-offs	(373)	(384)	(563)	(779)
Loan recoveries	30	228	152	267
Net loan charge-offs	(343)	(156)	(411)	(512)
Balance, end of period	$ 15,444	$ 14,317	$ 15,444	$ 14,317
Net charge-offs to average loans (annualized)	0.11%	0.06%	0.03%	0.10%
Allowance for loan losses to gross loans	1.19%	1.34%
Allowance for loan losses to nonperforming loans	293.75%	250.63%
Commercial [Member] \| Owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 3,052	$ 2,493	$ 2,843	$ 2,347
Provision for loan losses	(88)	304	121	455
Loan charge-offs				(5)
Loan recoveries
Net loan charge-offs				(5)
Balance, end of period	2,964	2,797	2,964	2,797
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	2,967	3,236	2,778	3,187
Provision for loan losses	255	(250)	623	(128)
Loan charge-offs	(253)		(433)	(75)
Loan recoveries	12	25	13	27
Net loan charge-offs	(241)	25	(420)	(48)
Balance, end of period	2,981	3,011	2,981	3,011
Commercial [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	334	442	295	338
Provision for loan losses	16	(49)	55	55
Loan charge-offs		(42)		(42)
Loan recoveries
Net loan charge-offs		(42)		(42)
Balance, end of period	350	351	350	351
Commercial [Member] \| Business [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	3,823	3,639	4,123	3,800
Provision for loan losses	139	488	(182)	330
Loan charge-offs	(120)	(311)	(130)	(348)
Loan recoveries	15	203	46	237
Net loan charge-offs	(105)	(108)	(84)	(111)
Balance, end of period	3,857	4,019	3,857	4,019
Consumer [Member] \| Real Estate [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	2,830	2,131	2,780	2,070
Provision for loan losses	240	170	200	418
Loan charge-offs				(187)
Loan recoveries	(9)		81
Net loan charge-offs	(9)		81	(187)
Balance, end of period	3,061	2,301	3,061	2,301
Consumer [Member] \| Home equity [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	1,619	1,263	1,475	1,202
Provision for loan losses	(23)	40	121	101
Loan charge-offs		(7)		(7)
Loan recoveries	12		12
Net loan charge-offs	12	(7)	12	(7)
Balance, end of period	1,608	1,296	1,608	1,296
Consumer [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	289	351	252	313
Provision for loan losses	39	(139)	76	(101)
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	328	212	328	212
Consumer [Member] \| Other [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	373	343	309	372
Provision for loan losses	(78)	11	(14)	70
Loan charge-offs		(24)		(115)
Loan recoveries				3
Net loan charge-offs		(24)		(112)
Balance, end of period	$ 295	$ 330	$ 295	$ 330

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

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- Definition

Allowance for loan losses as a percentage of gross loans.

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- Definition

Allowance for credit losses as a percentage of nonperforming loans.

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- Definition

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

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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.

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- Definition

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

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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://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=66008989&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=66902209&loc=d3e3602-108585

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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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