Loans and Leases - Summary of Troubled Debt Restructurings by Class of Loans (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	679	613
Pre-Modification Outstanding Recorded Investment	$ 12,220	$ 10,554
Post-Modification Outstanding Recorded Investment	$ 11,222	$ 9,818
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	4	3
Pre-Modification Outstanding Recorded Investment	$ 778	$ 1,165
Post-Modification Outstanding Recorded Investment	$ 737	$ 960
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	3	1
Pre-Modification Outstanding Recorded Investment	$ 1,727	$ 5
Post-Modification Outstanding Recorded Investment	$ 1,504	$ 4
Total Commercial Loans and Leases [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	7	4
Pre-Modification Outstanding Recorded Investment	$ 2,505	$ 1,170
Post-Modification Outstanding Recorded Investment	$ 2,241	$ 964
Direct Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	527	489
Pre-Modification Outstanding Recorded Investment	$ 6,090	$ 6,712
Post-Modification Outstanding Recorded Investment	$ 5,566	$ 6,314
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	45	45
Pre-Modification Outstanding Recorded Investment	$ 2,155	$ 1,667
Post-Modification Outstanding Recorded Investment	$ 2,081	$ 1,660
Indirect Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	19	17
Pre-Modification Outstanding Recorded Investment	$ 51	$ 55
Post-Modification Outstanding Recorded Investment	$ 51	$ 48
Consumer Lines of Credit [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	81	58
Pre-Modification Outstanding Recorded Investment	$ 1,419	$ 950
Post-Modification Outstanding Recorded Investment	$ 1,283	$ 832

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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