Loans and Leases - Schedule of Subsequently Defaulted TDRs (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) SecurityLoan	Mar. 31, 2018 USD ($) SecurityLoan
Accounts, Notes, Loans and Financing Receivable
Threshold period for loans in default (in days)	30 days
TDRs \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	116	65
Pre-modification Outstanding Recorded Investment	$ 34,120	$ 30,616
Post-modification Outstanding Recorded Investment	$ 31,429	$ 27,200
Number of loans \| SecurityLoan	70	122
Recorded investment	$ 10,597	$ 24,673
TDRs \| Commercial Loans \| Commercial real estate - Construction \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	1	1
Pre-modification Outstanding Recorded Investment	$ 39	$ 1,950
Post-modification Outstanding Recorded Investment	$ 39	$ 1,049
Number of loans \| SecurityLoan	1	0
Recorded investment	$ 939	$ 0
TDRs \| Commercial Loans \| Commercial real estate - owner-occupied \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	4	2
Pre-modification Outstanding Recorded Investment	$ 6,904	$ 10,691
Post-modification Outstanding Recorded Investment	$ 4,661	$ 9,324
Number of loans \| SecurityLoan	3	3
Recorded investment	$ 640	$ 10,187
TDRs \| Commercial Loans \| Commercial real estate - non-owner-occupied \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	7	9
Pre-modification Outstanding Recorded Investment	$ 2,990	$ 1,089
Post-modification Outstanding Recorded Investment	$ 2,968	$ 1,091
Number of loans \| SecurityLoan	7	9
Recorded investment	$ 825	$ 492
TDRs \| Commercial Loans \| Commercial and industrial \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	23	18
Pre-modification Outstanding Recorded Investment	$ 17,382	$ 14,429
Post-modification Outstanding Recorded Investment	$ 17,040	$ 13,314
Number of loans \| SecurityLoan	10	29
Recorded investment	$ 3,933	$ 9,708
TDRs \| Residential Mortgage \| Residential mortgage \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	10	0
Pre-modification Outstanding Recorded Investment	$ 1,741	$ 0
Post-modification Outstanding Recorded Investment	$ 1,738	$ 0
Number of loans \| SecurityLoan	13	6
Recorded investment	$ 1,108	$ 598
TDRs \| Consumer and Other Loans \| Consumer - Home equity \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	33	14
Pre-modification Outstanding Recorded Investment	$ 4,277	$ 1,809
Post-modification Outstanding Recorded Investment	$ 4,233	$ 1,795
Number of loans \| SecurityLoan	16	24
Recorded investment	$ 2,891	$ 2,331
TDRs \| Consumer and Other Loans \| Consumer - Other \| TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of Loans \| SecurityLoan	38	21
Pre-modification Outstanding Recorded Investment	$ 787	$ 648
Post-modification Outstanding Recorded Investment	$ 750	$ 627
Number of loans \| SecurityLoan	20	51
Recorded investment	$ 261	$ 1,357

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Number of financing receivables that have been 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
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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