Loans and Leases - Schedule of Modified TDRs (Detail) - TDRs Occurring during the Period - TDRs - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Modifications
Extended maturities	$ 2,450	$ 9,014
Maturity and interest rate adjustment	706	468
Movement to or extension of interest-rate only payments	46	12
Interest rate adjustment	3,878	0
Financing Receivable Modifications Forbearance	1,111	6,510
Other concession(s)	1,604	15,425
TDRs during period	9,795	31,429
Commercial Loans \| Real estate - construction
Financing Receivable, Modifications
TDRs during period	86	39
Commercial Loans \| Real estate - owner-occupied
Financing Receivable, Modifications
TDRs during period	2,558	4,661
Commercial Loans \| Real estate - non-owner-occupied
Financing Receivable, Modifications
TDRs during period	3,820	2,968
Commercial Loans \| Commercial and industrial
Financing Receivable, Modifications
TDRs during period	1,367	17,040
Residential mortgage \| Residential mortgage
Financing Receivable, Modifications
TDRs during period	413	1,738
Consumer and other loans \| Consumer - Home equity
Financing Receivable, Modifications
TDRs during period	1,482	4,233
Consumer and other loans \| Consumer - Other
Financing Receivable, Modifications
TDRs during period	$ 69	$ 750

Amount of troubled debt restructurings that were modified in the current period based on an extension of maturity.

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Amount of troubled debt restructurings that were modified in the current period based on an extension of interest-only payments beyond the original interest-only period.

+ References

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Amount of troubled debt restructurings that were modified in the current period based on a forbearance.

+ References

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Financing Receivable Modifications, Interest Rate Adjustment

+ References

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Amount of troubled debt restructurings that were modified in the current period based on an extension of maturity and a change in interest rate.

+ References

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Financing receivable, modifications, other concession(s).

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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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