Loans, Allowance for Loan Losses and Credit Quality (Modifications which occurred during the period & change in recorded investment) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) contract	Jun. 30, 2016 USD ($) contract	Jun. 30, 2017 USD ($) contract	Jun. 30, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	25	17	37	29
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 4,110	$ 2,169	$ 5,407	$ 3,558
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 4,124	$ 2,169	$ 5,421	$ 3,600
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	6	4	8	7
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 1,299	$ 253	$ 1,379	$ 528
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 1,299	$ 253	$ 1,379	$ 528
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	2	4	6	6
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 950	$ 918	$ 1,884	$ 1,343
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 950	$ 918	$ 1,884	$ 1,343
Small Business [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	4	2	8	2
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 121	$ 109	$ 264	$ 109
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 121	$ 109	$ 264	$ 109
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	5	3	5	5
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 889	$ 744	$ 889	$ 1,167
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 900	$ 744	$ 900	$ 1,209
Consumer - Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	8	3	10	4
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 851	$ 123	$ 991	$ 304
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 854	$ 123	$ 994	$ 304
Consumer - Other [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract		1		5
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 22		$ 107
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 22		$ 107

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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