Loans Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Satisfactory
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	$ 532,307	$ 492,629	$ 486,600
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	2,795	8,367	11,746
Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	30,166	35,805	33,719
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	807	0	0
Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	1,338,151	1,212,103	1,172,264
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	4,573	4,364	2,887
Commercial | Satisfactory
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	120,622	95,722	93,903
Commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	1,394	1,359	1,274
Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	3,344	8,074	7,877
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	411,685	396,907	392,697
Commercial Real Estate Portfolio Segment | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	1,401	7,008	10,472
Commercial Real Estate Portfolio Segment | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	26,822	27,731	25,842
Commercial Real Estate Portfolio Segment | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	807	0	0
Consumer Loans Financing | Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	591,499	536,614	523,171
Consumer Loans Financing | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	530	747	532
Residential | Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	746,652	675,489	649,093
Residential | Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Net	$ 4,043	$ 3,617	$ 2,355