Loans and the Allowance for Loan Losses - Loans Outstanding by Category (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Loans And Leases Receivable Disclosure [Line Items]
Total loans	$ 1,401,208	$ 1,350,899
Residential Mortgage
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	955	1,042
Total loans	549,982	538,920
Residential Mortgage \| Mortgages - Fixed Rate
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	299,231	298,851
Residential Mortgage \| Mortgages - Adjustable Rate
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	249,796	239,027
Commercial Mortgage
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	191	199
Total loans	662,613	633,649
Commercial Mortgage \| Construction
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	36,890	35,904
Commercial Mortgage \| Mortgages - Nonowner Occupied
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	587,183	562,203
Commercial Mortgage \| Mortgages - Owner Occupied
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	38,349	35,343
Home Equity
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	251	255
Total loans	71,853	74,444
Home Equity \| Home Equity - Lines of Credit
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	67,168	70,326
Home Equity \| Home Equity - Term Loans
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	4,434	3,863
Commercial & Industrial
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	80,206	65,305
Deferred costs (fees) net of unearned fees	(54)	(10)
Total loans	80,152	65,295
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	15	16
Total loans	36,608	38,591
Consumer \| Secured
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	35,461	37,272
Consumer \| Unsecured
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	$ 1,132	$ 1,303

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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