Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($) Contract	Sep. 30, 2016 USD ($) Contract	Sep. 30, 2017 USD ($) Contract	Sep. 30, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number \| Contract	2	2	4	3
Balance \| $	$ 88	$ 174	$ 203	$ 524
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| Contract	2	1	3	1
Balance \| $	$ 88	$ 62	$ 141	$ 62
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| Contract		1	1	2
Balance \| $		$ 112	$ 62	$ 462

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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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