Loans, Allowance for Loan Losses and Credit Quality (Modifications which occurred during the period & change in recorded investment) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	5	8	9	16
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 448	$ 908	$ 784	$ 1,974
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 453	$ 928	$ 789	$ 1,994
Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	2	2	2
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 87	$ 126	$ 184	$ 126
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 87	$ 126	$ 184	$ 126
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	1	2	2
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 133	$ 205	$ 283	$ 650
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 133	$ 205	$ 283	$ 650
Small Business [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1		2
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 19		$ 33
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 19		$ 33
Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	3	1	4
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 163	$ 503	$ 163	$ 652
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 168	$ 523	$ 168	$ 672
Consumer Home Equity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	2	2	8
TROUBLED DEBT RESTRUCTURINGS:
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 46	$ 74	$ 121	$ 546
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 46	$ 74	$ 121	$ 546

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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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