Allowance for Loan Losses Allowance for Loan Losses (Details 4) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Financing Receivable Portfolio Segment [Domain]
Financing Receivable, Modifications [Line Items]
Added	$ 42	$ 109	$ 478	$ 382
Charged Off	(172)	(13)	(283)	(220)
Payments	(430)	(365)	(1,336)	(1,136)
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	3,061	3,453	3,386	3,584
Added	0	0	0	0
Charged Off	0	0	0	0
Payments	(153)	(71)	(478)	(202)
Ending Balance	2,908	3,382	2,908	3,382
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	4,198	5,033	4,447	5,593
Added	0	0	227	123
Charged Off	(155)	0	(195)	(181)
Payments	(222)	(239)	(658)	(741)
Ending Balance	3,821	4,794	3,821	4,794
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	725	669	732	683
Added	42	109	251	259
Charged Off	(17)	(13)	(88)	(39)
Payments	(55)	(55)	(200)	(193)
Ending Balance	$ 695	$ 710	$ 695	$ 710

Financing Receivable, Impaired, Troubled Debt Restructuring, Additions During Period

No definition available.

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- Definition

Financing Receivable, Impaired, Troubled Debt Restructuring, Payments During Period

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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