Loans - Past-due Status of Loans by Class (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Schedule of Financing Receivables [Line Items]
All Past Due	$ 11,958	$ 11,863	$ 12,885
Current	927,211	905,701	856,029
Total	939,169	917,564	868,914
90 Days & Accruing	184	181	224
Commercial real estate
Schedule of Financing Receivables [Line Items]
All Past Due	798	860	2,362
Current	241,223	241,451	237,825
Total	242,021	242,311	240,187
90 Days & Accruing	0	0	0
Commercial construction
Schedule of Financing Receivables [Line Items]
All Past Due	229	249	208
Current	34,454	30,683	21,478
Total	34,683	30,932	21,686
90 Days & Accruing	0	0	0
Commercial other
Schedule of Financing Receivables [Line Items]
All Past Due	994	1,193	1,846
Current	114,461	103,338	95,430
Total	115,455	104,531	97,276
90 Days & Accruing	0	0	0
Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	26,277	20,424	17,790
Total	26,277	20,424	17,790
90 Days & Accruing	0	0	0
Residential term
Schedule of Financing Receivables [Line Items]
All Past Due	8,243	7,003	6,982
Current	375,626	377,029	365,497
Total	383,869	384,032	372,479
90 Days & Accruing	100	101	137
Residential construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	13,036	12,160	12,360
Total	13,036	12,160	12,360
90 Days & Accruing	0	0	0
Home equity line of credit
Schedule of Financing Receivables [Line Items]
All Past Due	1,457	2,122	1,336
Current	102,643	101,399	90,866
Total	104,100	103,521	92,202
90 Days & Accruing	0	0	29
Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	237	436	151
Current	19,491	19,217	14,783
Total	19,728	19,653	14,934
90 Days & Accruing	84	80	58
30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	5,219	2,746	4,291
30-59 Days Past Due \| Commercial real estate
Schedule of Financing Receivables [Line Items]
All Past Due	491	346	1,186
30-59 Days Past Due \| Commercial construction
Schedule of Financing Receivables [Line Items]
All Past Due	21	0	0
30-59 Days Past Due \| Commercial other
Schedule of Financing Receivables [Line Items]
All Past Due	135	336	231
30-59 Days Past Due \| Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
30-59 Days Past Due \| Residential term
Schedule of Financing Receivables [Line Items]
All Past Due	3,948	1,140	2,557
30-59 Days Past Due \| Residential construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
30-59 Days Past Due \| Home Equity Loan [Member]
Schedule of Financing Receivables [Line Items]
All Past Due	488	621	250
30-59 Days Past Due \| Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	136	303	67
60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,561	3,631	1,286
60-89 Days Past Due \| Commercial real estate
Schedule of Financing Receivables [Line Items]
All Past Due	0	107	55
60-89 Days Past Due \| Commercial construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	41	0
60-89 Days Past Due \| Commercial other
Schedule of Financing Receivables [Line Items]
All Past Due	2	543	231
60-89 Days Past Due \| Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
60-89 Days Past Due \| Residential term
Schedule of Financing Receivables [Line Items]
All Past Due	1,438	2,118	933
60-89 Days Past Due \| Residential construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
60-89 Days Past Due \| Home Equity Loan [Member]
Schedule of Financing Receivables [Line Items]
All Past Due	105	769	40
60-89 Days Past Due \| Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	16	53	27
Equal to Greater than 90 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	5,178	5,486	7,308
Equal to Greater than 90 Days Past Due \| Commercial real estate
Schedule of Financing Receivables [Line Items]
All Past Due	307	407	1,121
Equal to Greater than 90 Days Past Due \| Commercial construction
Schedule of Financing Receivables [Line Items]
All Past Due	208	208	208
Equal to Greater than 90 Days Past Due \| Commercial other
Schedule of Financing Receivables [Line Items]
All Past Due	857	314	1,384
Equal to Greater than 90 Days Past Due \| Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Equal to Greater than 90 Days Past Due \| Residential term
Schedule of Financing Receivables [Line Items]
All Past Due	2,857	3,745	3,492
Equal to Greater than 90 Days Past Due \| Residential construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Equal to Greater than 90 Days Past Due \| Home Equity Loan [Member]
Schedule of Financing Receivables [Line Items]
All Past Due	864	732	1,046
Equal to Greater than 90 Days Past Due \| Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	$ 85	$ 80	$ 57

Loans - Past-due Status of Loans by Class (Details) (USD $)
In Thousands, unless otherwise specified

Mar. 31, 2015

Dec. 31, 2014

Mar. 31, 2014

Schedule of Financing Receivables [Line Items]