Loans, Allowance for Credit Losses and Credit Quality Schedule of Debtor Troubled Debt Restructurings, Subsequent Period (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) contract	Mar. 31, 2019 USD ($) contract
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	5	2
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 1,098	$ 225
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 1,106	$ 225
Commercial And Industrial [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	2
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 268
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 268
Commercial Real Estate [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 604	$ 150
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 604	$ 150
Small Business [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 49
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 25
Residential Real Estate [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 177
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 209
Home Equity Line of Credit [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract		1
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 75
Financing Receivable, Troubled Debt Restructuring, Postmodification		$ 75

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

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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