Loans and Allowance for Loan Losses - Schedule of Loans Modified and Considered Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) SecurityLoan	Dec. 31, 2015 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	28	23
Pre-Modification Recorded Investment	$ 4,857	$ 1,428
Post-Modification Recorded Investment	$ 4,857	$ 1,428
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	15	8
Pre-Modification Recorded Investment	$ 3,208	$ 447
Post-Modification Recorded Investment	$ 3,208	$ 447
Agriculture [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan		3
Pre-Modification Recorded Investment		$ 128
Post-Modification Recorded Investment		$ 128
Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	6	5
Pre-Modification Recorded Investment	$ 1,460	$ 598
Post-Modification Recorded Investment	$ 1,460	$ 598
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	7	7
Pre-Modification Recorded Investment	$ 189	$ 255
Post-Modification Recorded Investment	$ 189	$ 255

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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=66008989&loc=SL6953676-111524

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

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