Allowance for Credit Losses and Credit Quality - Summary of TDR Modifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	$ 10,452	$ 4,815
Post-modification Investment	10,363	4,796
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	5,857	1,764
Post-modification Investment	5,857	1,764
Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	5,751	1,195
Post-modification Investment	5,751	1,195
Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	106	569
Post-modification Investment	106	569
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	4,595	3,051
Post-modification Investment	4,506	3,032
Consumer \| Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	3,222	1,385
Post-modification Investment	3,157	1,378
Consumer \| Consumer installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	376	0
Post-modification Investment	353	0
Consumer \| Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	997	1,666
Post-modification Investment	$ 996	$ 1,654

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=118936363&loc=SL6953676-111524

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- Definition

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

+ References

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