Loans and Allowance for Loan Losses - Schedule of Loans by Class Modified as Troubled Debt Restructuring (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) SecurityLoan	Mar. 31, 2016 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	14	26
Pre-modification Outstanding Recorded Investment	$ 11,930	$ 11,536
Post-modification Outstanding Recorded Investment	$ 11,930	$ 11,536
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	6	10
Pre-modification Outstanding Recorded Investment	$ 9,442	$ 1,542
Post-modification Outstanding Recorded Investment	$ 9,442	$ 1,542
Other [Member] \| Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan		7
Pre-modification Outstanding Recorded Investment		$ 9,476
Post-modification Outstanding Recorded Investment		$ 9,476
Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	3	1
Pre-modification Outstanding Recorded Investment	$ 564	$ 133
Post-modification Outstanding Recorded Investment	$ 564	$ 133
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=66008989&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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