Loans Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Satisfactory
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	$ 559,331	$ 542,323	$ 532,307
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	5,949	1,518	2,795
Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	31,147	28,849	30,166
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	807	807	807
Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	1,525,879	1,373,752	1,338,151
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	2,987	3,727	4,573
Commercial | Satisfactory
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	119,217	124,961	120,622
Commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	5,949	1,341	1,394
Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	1,946	2,947	3,344
Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	0	0	0
Commercial Real Estate Portfolio Segment | Satisfactory
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	440,114	417,362	411,685
Commercial Real Estate Portfolio Segment | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	0	177	1,401
Commercial Real Estate Portfolio Segment | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	29,201	25,902	26,822
Commercial Real Estate Portfolio Segment | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	807	807	807
Consumer Loans Financing | Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	693,648	602,168	591,499
Consumer Loans Financing | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	540	659	530
Residential | Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	832,231	771,584	746,652
Residential | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	$ 2,447	$ 3,068	$ 4,043