Loans and Leases - Summary of Troubled Debt Restructurings by Class of Loans (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) Contract	Mar. 31, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	192	168
Pre-Modification Outstanding Recorded Investment	$ 9,556	$ 2,705
Post-Modification Outstanding Recorded Investment	$ 7,201	$ 2,597
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	4	2
Pre-Modification Outstanding Recorded Investment	$ 778	$ 312
Post-Modification Outstanding Recorded Investment	$ 760	$ 196
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	2
Pre-Modification Outstanding Recorded Investment	$ 5,565
Post-Modification Outstanding Recorded Investment	$ 3,279
Total Commercial Loans and Leases [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	6	2
Pre-Modification Outstanding Recorded Investment	$ 6,343	$ 312
Post-Modification Outstanding Recorded Investment	$ 4,039	$ 196
Direct Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	145	131
Pre-Modification Outstanding Recorded Investment	$ 1,991	$ 1,526
Post-Modification Outstanding Recorded Investment	$ 1,961	$ 1,484
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	18	14
Pre-Modification Outstanding Recorded Investment	$ 968	$ 581
Post-Modification Outstanding Recorded Investment	$ 951	$ 631
Indirect Installment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	3	5
Pre-Modification Outstanding Recorded Investment	$ 11	$ 16
Post-Modification Outstanding Recorded Investment	$ 12	$ 16
Consumer Lines of Credit [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	20	16
Pre-Modification Outstanding Recorded Investment	$ 243	$ 270
Post-Modification Outstanding Recorded Investment	$ 238	$ 270

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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=49124121&loc=SL6953676-111524

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