Loans and the Allowance for Loan Losses - Loans Outstanding by Category (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Loans And Leases Receivable Disclosure [Line Items]
Total loans	$ 2,096,550	$ 1,559,772
Residential Mortgage
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	1,722	1,408
Total loans	938,559	604,331
Residential Mortgage \| Construction
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	28,437
Residential Mortgage \| Mortgages - Fixed Rate
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	409,706	293,267
Residential Mortgage \| Mortgages - Adjustable Rate
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	498,694	309,656
Commercial Mortgage
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	124	82
Total loans	905,442	757,957
Commercial Mortgage \| Construction
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	51,816	44,146
Commercial Mortgage \| Mortgages - Nonowner Occupied
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	788,982	654,394
Commercial Mortgage \| Mortgages - Owner Occupied
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	64,520	59,335
Home Equity
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	237	250
Total loans	85,814	69,336
Home Equity \| Home Equity - Lines of Credit
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	79,814	63,421
Home Equity \| Home Equity - Term Loans
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	5,763	5,665
Commercial & Industrial
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	134,338	93,728
Deferred costs (fees) net of unearned fees	(31)	(16)
Total loans	134,307	93,712
Consumer
Loans And Leases Receivable Disclosure [Line Items]
Deferred costs (fees) net of unearned fees	13	13
Total loans	32,428	34,436
Consumer \| Secured
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	31,380	33,252
Consumer \| Unsecured
Loans And Leases Receivable Disclosure [Line Items]
Loans outstanding by category gross	$ 1,035	$ 1,171

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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-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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