Loans, Allowance for Loan Losses and Credit Quality (Impaired Loans by Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 1,187	$ 1,342	$ 1,536
Related Allowance	1,187	1,342
Impaired Financing Receivable, Recorded Investment, Total	68,080	72,801
Impaired Financing Receivable, Unpaid Principal Balance	76,936	79,276
WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	55,726	57,373
Unpaid Principal Balance	63,378	62,867
Related Allowance	0	0
WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	12,354	15,428
Unpaid Principal Balance	13,558	16,409
Commercial and Industrial [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	8	10	70
Commercial and Industrial [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	32,319	34,267
Unpaid Principal Balance	38,662	38,329
Related Allowance	0	0
Commercial and Industrial [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	223	376
Unpaid Principal Balance	223	376
Commercial Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	74	42	166
Commercial Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	12,858	13,245
Unpaid Principal Balance	13,719	14,374
Related Allowance	0	0
Commercial Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	2,158	3,393
Unpaid Principal Balance	2,282	3,399
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	1	1	1
Small Business [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	645	556
Unpaid Principal Balance	744	619
Related Allowance	0	0
Small Business [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	158	147
Unpaid Principal Balance	166	153
Residential Real Estate [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	859	1,007	1,036
Residential Real Estate [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	4,803	4,264
Unpaid Principal Balance	4,945	4,397
Related Allowance	0	0
Residential Real Estate [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	7,902	9,420
Unpaid Principal Balance	8,752	10,154
Consumer Home Equity [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	231	265	243
Consumer Home Equity [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	5,037	4,950
Unpaid Principal Balance	5,243	5,056
Related Allowance	0	0
Consumer Home Equity [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	1,722	1,876
Unpaid Principal Balance	1,942	2,110
Consumer - Other [Member]
Impaired loans by loan portfolio
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	14	17	$ 20
Consumer - Other [Member] \| WITH NO RELATED ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	64	91
Unpaid Principal Balance	65	92
Related Allowance	0	0
Consumer - Other [Member] \| WITH AN ALLOWANCE RECORDED: [Member]
Impaired loans by loan portfolio
Recorded Investment	191	216
Unpaid Principal Balance	$ 193	$ 217

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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