Allowance for Loan and Lease Losses and Credit Quality - Summary of TDR Modifications (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	$ 2,839	$ 3,126	$ 39,130	$ 11,416
Post-modification Investment	2,838	3,113	39,111	11,344
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	0	11	31,518	5,239
Post-modification Investment	0	11	31,518	5,239
Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	0	11	0	11
Post-modification Investment	0	11	0	11
Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	0	0	31,518	5,228
Post-modification Investment	0	0	31,518	5,228
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	2,839	3,115	7,612	6,177
Post-modification Investment	2,838	3,102	7,593	6,105
Consumer \| Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	1,724	2,132	4,023	4,385
Post-modification Investment	1,723	2,119	4,016	4,315
Consumer \| Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-modification Investment	1,115	983	3,589	1,792
Post-modification Investment	$ 1,115	$ 983	$ 3,577	$ 1,790

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.

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

+ References

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