Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 15,444	$ 14,317	$ 14,855	$ 13,629
Provision for loan losses	500	825	1,500	2,025
Loan charge-offs	(399)	(683)	(962)	(1,462)
Loan recoveries	34	19	186	286
Net loan charge-offs	(365)	(664)	(776)	(1,176)
Balance, end of period	$ 15,579	$ 14,478	$ 15,579	$ 14,478
Net charge-offs to average loans (annualized)	0.11%	0.24%	0.08%	0.15%
Allowance for loan losses to gross loans	1.17%	1.30%
Allowance for loan losses to nonperforming loans	278.05%	258.30%
Commercial [Member] \| Owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 2,964	$ 2,797	$ 2,843	$ 2,347
Provision for loan losses	(141)	98	(20)	553
Loan charge-offs				(5)
Loan recoveries
Net loan charge-offs				(5)
Balance, end of period	2,823	2,895	2,823	2,895
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	2,981	3,011	2,778	3,187
Provision for loan losses	634	47	1,257	(81)
Loan charge-offs		(25)	(433)	(100)
Loan recoveries	1	5	14	32
Net loan charge-offs	1	(20)	(419)	(68)
Balance, end of period	3,616	3,038	3,616	3,038
Commercial [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	350	350	295	338
Provision for loan losses	(122)	(53)	(67)	2
Loan charge-offs				(43)
Loan recoveries
Net loan charge-offs				(43)
Balance, end of period	228	297	228	297
Commercial [Member] \| Business [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	3,857	4,019	4,123	3,800
Provision for loan losses	213	337	31	666
Loan charge-offs	(388)	(515)	(518)	(862)
Loan recoveries	31	13	77	250
Net loan charge-offs	(357)	(502)	(441)	(612)
Balance, end of period	3,713	3,854	3,713	3,854
Consumer [Member] \| Real estate [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	3,061	2,302	2,780	2,070
Provision for loan losses	160	215	359	641
Loan charge-offs				(194)
Loan recoveries	1		83
Net loan charge-offs	1		83	(194)
Balance, end of period	3,222	2,517	3,222	2,517
Consumer [Member] \| Home equity [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	1,608	1,296	1,475	1,202
Provision for loan losses	(196)	119	(75)	236
Loan charge-offs		(43)		(66)
Loan recoveries			12
Net loan charge-offs		(43)	12	(66)
Balance, end of period	1,412	1,372	1,412	1,372
Consumer [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	328	212	252	313
Provision for loan losses	(47)	(5)	29	(106)
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	281	207	281	207
Consumer [Member] \| Other [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	295	330	309	372
Provision for loan losses	(1)	67	(14)	114
Loan charge-offs	(11)	(100)	(11)	(192)
Loan recoveries	1	1		4
Net loan charge-offs	(10)	(99)	(11)	(188)
Balance, end of period	$ 284	$ 298	$ 284	$ 298

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.

+ 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

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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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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=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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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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