Loans - Schedule of Loan Modifications (Detail)	6 Months Ended
Jun. 30, 2020 USD ($) Loan	Jun. 30, 2019 USD ($) Contract
Financing Receivable Modifications [Line Items]
Number of Loans \| Contract		1
Balance	$ 0	$ 0
CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	813
Balance	$ 431,283,000
Weighted Average Interest Rate	4.57%
Commercial and Agriculture [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	229
Balance	$ 47,686,000
Weighted Average Interest Rate	4.56%
Commercial Real Estate Owner Occupied [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	193
Balance	$ 91,831,000
Weighted Average Interest Rate	4.82%
Commercial Real Estate Non Owner Occupied [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Contract		1
Commercial Real Estate Non Owner Occupied [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	179
Balance	$ 234,543,000
Weighted Average Interest Rate	4.47%
Residential Real Estate [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	170
Balance	$ 29,012,000
Weighted Average Interest Rate	4.67%
Real Estate Construction [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	18
Balance	$ 26,296,000
Weighted Average Interest Rate	4.39%
Farm Real Estate [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	9
Balance	$ 1,783,000
Weighted Average Interest Rate	4.94%
Consumer and Other [Member] \| CARES Act [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	15
Balance	$ 132,000
Weighted Average Interest Rate	8.01%

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+ References

No definition available.

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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-Publisher FASB
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-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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