Loans and Allowance for Loan Losses - Schedule of Loans by Class Modified as Troubled Debt Restructuring (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($) SecurityLoan	Jun. 30, 2016 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	27	36
Pre-modification Outstanding Recorded Investment	$ 29,733	$ 22,534
Post-modification Outstanding Recorded Investment	$ 29,733	$ 22,534
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	6	16
Pre-modification Outstanding Recorded Investment	$ 9,442	$ 11,233
Post-modification Outstanding Recorded Investment	$ 9,442	$ 11,233
Other [Member] \| Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	10	9
Pre-modification Outstanding Recorded Investment	$ 17,429	$ 10,581
Post-modification Outstanding Recorded Investment	$ 17,429	$ 10,581
Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	6	3
Pre-modification Outstanding Recorded Investment	$ 938	$ 335
Post-modification Outstanding Recorded Investment	$ 938	$ 335
Consumer - Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	5	8
Pre-modification Outstanding Recorded Investment	$ 1,924	$ 385
Post-modification Outstanding Recorded Investment	$ 1,924	$ 385

The number of loans included in the loan portfolio.

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+ References

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- Definition

Post-modification amount of investment in financing receivables 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=84173941&loc=SL6953676-111524

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

+ References

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