Loans and Leases - Schedule of Modified TDRs (Detail) - TDRs Occurring during the Period - TDRs - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Modifications
Extended maturities	$ 11,741	$ 23,262	$ 26,561
Interest rate adjustment	68	99	24
Maturity and interest rate adjustment	1,729	554	4,932
Movement to or extension of interest-rate only payments	1,791	881	4,161
Forbearance	22,319	4,432	7,226
Other concession(s)	20,226	23,943	27,555
Total	$ 57,874	$ 53,171	$ 70,459

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.

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No definition available.

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

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Financing Receivable Modifications, Interest Rate Adjustment

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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.

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Financing receivable, modifications, other concession(s).

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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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