Loans and Leases - Schedule of Modified TDRs (Detail) - TDRs Occurring during the Period - TDRs - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Financing Receivable, Modifications
TDRs during period on accrual status	$ 16,500	$ 12,900
TDRs during period on non-accrual status	14,900	14,300
Extended maturities	9,014	5,619
Maturity and interest rate adjustment	468	108
Movement to or extension of interest-rate only payments	12	48
Interest rate adjustment	0	105
Financing Receivable Modifications Forbearance	6,510	12,886
Other concession(s)	15,425	8,434
TDRs during period	31,429	27,200
Commercial Loans \| Commercial real estate - Construction
Financing Receivable, Modifications
TDRs during period	39	1,049
Commercial Loans \| Commercial real estate - owner-occupied
Financing Receivable, Modifications
TDRs during period	4,661	9,324
Commercial Loans \| Commercial real estate - non-owner-occupied
Financing Receivable, Modifications
TDRs during period	2,968	1,091
Commercial Loans \| Commercial and industrial
Financing Receivable, Modifications
TDRs during period	17,040	13,314
Residential Mortgage \| Residential mortgage
Financing Receivable, Modifications
TDRs during period	1,738	0
Consumer and Other Loans \| Consumer - Home equity
Financing Receivable, Modifications
TDRs during period	4,233	1,795
Consumer and Other Loans \| Consumer - Other
Financing Receivable, Modifications
TDRs during period	$ 750	$ 627

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

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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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+ References

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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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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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