Imparied Loan Information by Portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 1,930	$ 2,416	$ 3,774
Related Allowance	1,930	2,416	3,774
Recorded Investment	51,410	58,035	72,055
Unpaid Principal Balance	54,822	61,887	75,817
Average Recorded Investment	51,678	62,202	76,523
Interest Income Recognized	1,993	3,242	3,968
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	183	412	1,150
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	204	197	765
Construction Loans [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0	0
Small Business [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	4	7	109
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	1,278	1,500	1,564
Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	238	262	116
Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	23	38	70
With No Related Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment	24,403	26,936	29,685
Unpaid Principal Balance	26,276	28,535	32,186
Average Recorded Investment	24,774	29,464	32,896
Interest Income Recognized	835	1,665	1,915
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment	2,613	3,005	7,147
Unpaid Principal Balance	3,002	3,278	7,288
Average Recorded Investment	3,024	4,557	7,338
Interest Income Recognized	71	258	338
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	12,008	15,982	14,283
Unpaid Principal Balance	13,128	17,164	15,891
Average Recorded Investment	11,676	16,703	15,728
Interest Income Recognized	375	1,025	1,075
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Construction Loans [Member]
Impaired loans by loan portfolio
Recorded Investment	304	311	100
Unpaid Principal Balance	305	311	408
Average Recorded Investment	308	311	1,105
Interest Income Recognized		13	43
Related Allowance	0	0	0
With No Related Allowance Recorded [Member] | Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment	527	692	1,474
Unpaid Principal Balance	618	718	1,805
Average Recorded Investment	584	772	1,854
Interest Income Recognized	22	45	121
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	3,874	2,439	1,972
Unpaid Principal Balance	4,033	2,502	2,026
Average Recorded Investment	3,958	2,493	2,021
Interest Income Recognized	157	102	95
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment	4,893	4,169	4,263
Unpaid Principal Balance	5,005	4,221	4,322
Average Recorded Investment	5,023	4,264	4,335
Interest Income Recognized	195	198	202
Related Allowance	0	0
With No Related Allowance Recorded [Member] | Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment	184	338	446
Unpaid Principal Balance	185	341	446
Average Recorded Investment	201	364	515
Interest Income Recognized	15	24	41
Related Allowance	0	0
With Allowance Recorded [Member]
Impaired loans by loan portfolio
Recorded Investment	27,007	31,099	42,370
Unpaid Principal Balance	28,546	33,352	43,631
Average Recorded Investment	26,904	32,738	43,627
Interest Income Recognized	1,158	1,577	2,053
With Allowance Recorded [Member] | Commercial and Industrial [Member]
Impaired loans by loan portfolio
Recorded Investment	2,534	1,649	2,001
Unpaid Principal Balance	2,648	1,859	2,045
Average Recorded Investment	2,848	2,032	2,572
Interest Income Recognized	48	98	125
With Allowance Recorded [Member] | Commercial Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	10,978	14,747	25,233
Unpaid Principal Balance	11,047	15,514	25,377
Average Recorded Investment	10,789	15,650	25,595
Interest Income Recognized	592	842	1,326
With Allowance Recorded [Member] | Small Business [Member]
Impaired loans by loan portfolio
Recorded Investment	494	396	429
Unpaid Principal Balance	523	458	462
Average Recorded Investment	535	456	459
Interest Income Recognized	30	32	28
With Allowance Recorded [Member] | Residential Real Estate [Member]
Impaired loans by loan portfolio
Recorded Investment	11,531	12,616	13,228
Unpaid Principal Balance	12,652	13,727	14,197
Average Recorded Investment	11,669	12,817	13,405
Interest Income Recognized	460	537	515
With Allowance Recorded [Member] | Home Equity [Member]
Impaired loans by loan portfolio
Recorded Investment	1,096	1,161	627
Unpaid Principal Balance	1,287	1,264	694
Average Recorded Investment	655	1,203	642
Interest Income Recognized	14	46	26
With Allowance Recorded [Member] | Consumer Portfolio Segment [Member]
Impaired loans by loan portfolio
Recorded Investment	374	530	852
Unpaid Principal Balance	389	530	856
Average Recorded Investment	408	580	954
Interest Income Recognized	$ 14	$ 22	$ 33