Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 14,855	$ 13,629
Provision for loan losses	500	625
Loan charge-offs	(190)	(394)
Loan recoveries	122	38
Net loan charge-offs	(68)	(356)
Balance, end of period	$ 15,287	$ 13,898
Net charge-offs to average loans (annualized)	0.02%	0.14%
Allowance for loan losses to gross loans	1.25%	1.34%
Allowance for loan losses to nonperforming loans	247.43%	224.56%
Commercial [Member] \| Owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 2,843	$ 2,347
Provision for loan losses	209	151
Loan charge-offs		(5)
Loan recoveries
Net loan charge-offs		(5)
Balance, end of period	3,052	2,493
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	2,778	3,187
Provision for loan losses	369	122
Loan charge-offs	(181)	(75)
Loan recoveries	1	2
Net loan charge-offs	(180)	(73)
Balance, end of period	2,967	3,236
Commercial [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	295	338
Provision for loan losses	39	104
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	334	442
Commercial [Member] \| Business [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	4,123	3,800
Provision for loan losses	(321)	(158)
Loan charge-offs	(9)	(36)
Loan recoveries	30	33
Net loan charge-offs	21	(3)
Balance, end of period	3,823	3,639
Consumer [Member] \| Real Estate [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	2,780	2,070
Provision for loan losses	(40)	248
Loan charge-offs		(187)
Loan recoveries	90
Net loan charge-offs	90	(187)
Balance, end of period	2,830	2,131
Consumer [Member] \| Home equity [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	1,475	1,202
Provision for loan losses	143	61
Loan charge-offs
Loan recoveries	1
Net loan charge-offs	1
Balance, end of period	1,619	1,263
Consumer [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	252	313
Provision for loan losses	37	38
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	289	351
Consumer [Member] \| Other [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	309	372
Provision for loan losses	64	59
Loan charge-offs		(91)
Loan recoveries		3
Net loan charge-offs		(88)
Balance, end of period	$ 373	$ 343

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

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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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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