Allowance for Credit Losses and Credit Quality - Summary of TDR Modifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	$ 5,695	$ 10,452
Post-modification Investment	5,695	10,363
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	4,191	5,857
Post-modification Investment	4,191	5,857
Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	2,491	5,751
Post-modification Investment	2,491	5,751
Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	1,700	106
Post-modification Investment	1,700	106
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	1,504	4,595
Post-modification Investment	1,504	4,506
Consumer \| Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	1,126	3,222
Post-modification Investment	1,126	3,157
Consumer \| Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	334	997
Post-modification Investment	334	996
Consumer \| Consumer installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	44	376
Post-modification Investment	$ 44	$ 353

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Amount, after troubled debt restructuring, of modified financing receivable.

+ 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=121611835&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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