Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 Contract	Jun. 30, 2016 USD ($) Contract	Jun. 30, 2017 USD ($) Contract	Jun. 30, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number \| Contract	0	1	2	1
Balance \| $		$ 350	$ 116	$ 350
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| Contract			1
Balance \| $			$ 53
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| Contract		1	1	1
Balance \| $		$ 350	$ 63	$ 350

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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