Allowance for Loan Losses - Composition of Allowance for Loans Losses, by Class (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	$ 974	$ 754	$ 1,803
Allowance for Loans Evaluated Collectively for Impairment	9,164	9,162	8,541
Total Allowance for Loan Losses	10,138	9,916	10,344	$ 11,514
Commercial \| Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	505	89	346
Allowance for Loans Evaluated Collectively for Impairment	3,483	3,031	3,186
Total Allowance for Loan Losses	3,988	3,120	3,532	4,602
Commercial \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	100	302	413
Allowance for Loans Evaluated Collectively for Impairment	296	278	410
Total Allowance for Loan Losses	396	580	823	575
Commercial \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	39	8	129
Allowance for Loans Evaluated Collectively for Impairment	1,741	1,444	1,376
Total Allowance for Loan Losses	1,780	1,452	1,505	2,276
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	18	17	15
Total Allowance for Loan Losses	18	17	15	15
Residential \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	44	24	20
Total Allowance for Loan Losses	44	24	20	21
Residential \| Term
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	304	326	519
Allowance for Loans Evaluated Collectively for Impairment	984	1,065	666
Total Allowance for Loan Losses	1,288	1,391	1,185	1,099
Home Equity LIne of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	26	29	396
Allowance for Loans Evaluated Collectively for Impairment	781	864	664
Total Allowance for Loan Losses	807	893	1,060	675
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	559	566	542
Total Allowance for Loan Losses	559	566	542	573
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loans Evaluated Individually for Impairment	0	0	0
Allowance for Loans Evaluated Collectively for Impairment	1,258	1,873	1,662
Total Allowance for Loan Losses	$ 1,258	$ 1,873	$ 1,662	$ 1,678

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ 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 (g)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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