Loans and Allowance for Loan Losses - Schedule of Loans Modified and Considered Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) SecurityLoan	Jun. 30, 2016 USD ($) SecurityLoan	Jun. 30, 2017 USD ($) SecurityLoan	Jun. 30, 2016 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	4	6	9	17
Pre-Modification Recorded Investment	$ 276	$ 384	$ 566	$ 3,507
Post-Modification Recorded Investment	$ 276	$ 384	$ 566	$ 3,507
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	2	4	6	11
Pre-Modification Recorded Investment	$ 90	$ 286	$ 324	$ 2,926
Post-Modification Recorded Investment	$ 90	$ 286	$ 324	$ 2,926
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	1		2	2
Pre-Modification Recorded Investment	$ 161		$ 217	$ 463
Post-Modification Recorded Investment	$ 161		$ 217	$ 463
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	1	2	1	4
Pre-Modification Recorded Investment	$ 25	$ 98	$ 25	$ 118
Post-Modification Recorded Investment	$ 25	$ 98	$ 25	$ 118

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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=84173941&loc=SL6953676-111524

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

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

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