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, 2019 USD ($) contract	Jun. 30, 2018 USD ($) contract	Jun. 30, 2019 USD ($) contract	Jun. 30, 2018 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	3	5	5	8
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 153	$ 379	$ 378	$ 1,066
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 153	$ 379	$ 378	$ 1,066
Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1		1
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 97		$ 97
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 97		$ 97
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	0	1	1
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 0	$ 150	$ 445
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 0	$ 150	$ 445
Small Business [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	2		2
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 56		$ 56
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 56		$ 56
Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract		1		1
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 149		$ 149
Financing Receivable, Troubled Debt Restructuring, Postmodification		$ 149		$ 149
Consumer Home Equity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	4	1	6
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 230	$ 75	$ 472
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 230	$ 75	$ 472

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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