Allowance for Loan Losses - Individual Evaluation of Impaired Loans and Related Allowance (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Modifications [Line Items]
Unpaid Principal Balance, With No Allowance Recorded	$ 4,670	$ 4,287
Recorded Investment, With No Allowance Recorded	4,670	4,287
Unpaid Principal Balance, With an Allowance Recorded	7,865	9,149
Recorded Investment, With an Allowance Recorded	7,865	9,149
Related Allowance, With an Allowance Recorded	817	909
Residential Properties
Financing Receivable Modifications [Line Items]
Unpaid Principal Balance, With No Allowance Recorded	675
Recorded Investment, With No Allowance Recorded	675
Commercial Real Estate
Financing Receivable Modifications [Line Items]
Unpaid Principal Balance, With No Allowance Recorded	1,642	4,037
Recorded Investment, With No Allowance Recorded	1,642	4,037
Unpaid Principal Balance, With an Allowance Recorded	1,282
Recorded Investment, With an Allowance Recorded	1,282
Related Allowance, With an Allowance Recorded	104
Commercial and Industrial Loans
Financing Receivable Modifications [Line Items]
Unpaid Principal Balance, With No Allowance Recorded	2,353	250
Recorded Investment, With No Allowance Recorded	2,353	250
Unpaid Principal Balance, With an Allowance Recorded	6,583	9,149
Recorded Investment, With an Allowance Recorded	6,583	9,149
Related Allowance, With an Allowance Recorded	$ 713	$ 909

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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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.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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