Allowance for Loan Losses Allowance for Loan Losses (Details 4) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Financing Receivable Portfolio Segment [Domain]
Financing Receivable, Modifications [Line Items]
Added	$ 181	$ 168
Charged Off	(52)	(56)
Payments	(244)	(519)
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	2,709	3,386
Added	0	0
Charged Off	0	0
Payments	(37)	(84)
Ending Balance	2,672	3,302
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	3,611	4,447
Added	107	0
Charged Off	(16)	(33)
Payments	(134)	(346)
Ending Balance	3,568	4,068
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Beginning Balance	714	732
Added	74	168
Charged Off	(36)	(23)
Payments	(73)	(89)
Ending Balance	$ 679	$ 788

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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