Loans, Allowance for Credit Losses and Credit Quality Schedule of Debtor Troubled Debt Restructurings, Subsequent Period (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract	Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	7	8	12
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 89	$ 1,655	$ 18,301	$ 2,753
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 89	$ 1,706	$ 18,301	$ 2,812
Commercial And Industrial [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1	1	3
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 40	$ 14,148	$ 308
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 40	$ 14,148	$ 308
Commercial Real Estate [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	4	5	5
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 1,170	$ 3,964	$ 1,774
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 1,170	$ 3,964	$ 1,774
Small Business [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	1	2	2
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 89	$ 63	$ 189	$ 112
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 89	$ 63	$ 189	$ 88
Residential Real Estate [Member]
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract		1		2
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 382		$ 559
Financing Receivable, Troubled Debt Restructuring, Postmodification		$ 433		$ 642

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=123577603&loc=SL6953676-111524

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