Loans and Allowance for Loan Losses - Internal Risk Rating Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	$ 1,340,921	$ 1,304,582	$ 1,156,573
Commercial and Non-Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	962,064	941,033	824,625
Commercial and Non-Residential Real Estate | Commercial Business
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	476,551	443,531
Commercial and Non-Residential Real Estate | Commercial Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	389,535	375,561
Commercial and Non-Residential Real Estate | Acquisition & Development
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	95,978	121,941
Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	310,713	294,929	260,513
Home Equity
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	58,675	59,015	59,526
Consumer
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	9,469	9,605	$ 11,909
Pass
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	1,312,255	1,280,713
Pass | Commercial and Non-Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	938,854	922,652
Pass | Commercial and Non-Residential Real Estate | Commercial Business
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	463,995	432,589
Pass | Commercial and Non-Residential Real Estate | Commercial Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	382,037	371,309
Pass | Commercial and Non-Residential Real Estate | Acquisition & Development
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	92,822	118,754
Pass | Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	306,347	290,602
Pass | Home Equity
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	57,767	58,100
Pass | Consumer
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	9,287	9,359
Special Mention
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	15,007	11,188
Special Mention | Commercial and Non-Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	11,400	7,540
Special Mention | Commercial and Non-Residential Real Estate | Commercial Business
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	6,238	5,290
Special Mention | Commercial and Non-Residential Real Estate | Commercial Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	4,985	2,071
Special Mention | Commercial and Non-Residential Real Estate | Acquisition & Development
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	177	179
Special Mention | Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	2,573	2,608
Special Mention | Home Equity
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	870	876
Special Mention | Consumer
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	164	164
Substandard
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	13,416	12,370
Substandard | Commercial and Non-Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	11,685	10,712
Substandard | Commercial and Non-Residential Real Estate | Commercial Business
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	6,318	5,652
Substandard | Commercial and Non-Residential Real Estate | Commercial Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	2,513	2,181
Substandard | Commercial and Non-Residential Real Estate | Acquisition & Development
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	2,854	2,879
Substandard | Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	1,675	1,600
Substandard | Home Equity
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	38	39
Substandard | Consumer
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	18	19
Doubtful
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	243	311
Doubtful | Commercial and Non-Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	125	129
Doubtful | Commercial and Non-Residential Real Estate | Commercial Business
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	0	0
Doubtful | Commercial and Non-Residential Real Estate | Commercial Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	0	0
Doubtful | Commercial and Non-Residential Real Estate | Acquisition & Development
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	125	129
Doubtful | Residential Real Estate
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	118	119
Doubtful | Home Equity
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	0	0
Doubtful | Consumer
Classes of the loan portfolio summarized by credit quality indicators:
Total Loans	$ 0	$ 63