Loans, Allowance for Loan Losses and Credit Quality (Impaired Loans by Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 1,073	$ 1,079	$ 1,187
Related Allowance	1,073	1,079
Impaired Financing Receivable, Recorded Investment, Total	54,163	59,060
Impaired Financing Receivable, Unpaid Principal Balance	66,217	68,514
WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	44,300	47,900
Unpaid Principal Balance	55,042	56,125
Related Allowance	0	0
WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	9,863	11,160
Unpaid Principal Balance	11,175	12,389
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	7	7	8
Commercial and Industrial [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	27,085	28,459
Unpaid Principal Balance	37,169	35,913
Related Allowance	0	0
Commercial and Industrial [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	266	370
Unpaid Principal Balance	266	370
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	74	37	74
Commercial Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	7,414	9,552
Unpaid Principal Balance	7,634	9,832
Related Allowance	0	0
Commercial Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	1,655	1,287
Unpaid Principal Balance	1,655	1,287
Construction Loans [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0		0
Small Business [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	38	1	1
Small Business [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	342	358
Unpaid Principal Balance	389	439
Related Allowance	0	0
Small Business [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	188	183
Unpaid Principal Balance	229	223
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	789	862	859
Residential Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	4,694	4,518
Unpaid Principal Balance	4,831	4,686
Related Allowance	0	0
Residential Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	6,657	8,188
Unpaid Principal Balance	7,765	9,217
Consumer Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	159	164	231
Consumer Home Equity [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	4,723	4,957
Unpaid Principal Balance	4,976	5,199
Related Allowance	0	0
Consumer Home Equity [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	966	991
Unpaid Principal Balance	1,127	1,149
Consumer - Other [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	6	8	$ 14
Consumer - Other [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	42	56
Unpaid Principal Balance	43	56
Related Allowance	0	0
Consumer - Other [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	131	141
Unpaid Principal Balance	$ 133	$ 143

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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-Publisher FASB
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