Loans - Schedule of Loan Modifications (Detail)	3 Months Ended
Mar. 31, 2020 USD ($) Loan	Mar. 31, 2019 Contract
Financing Receivable Modifications [Line Items]
Number of Loans \| Contract		1
Balance	$ 0
CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	66
Balance	$ 39,921,000
Weighted Average Interest Rate	4.82%
Commercial and Agriculture [Member] \| CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	26
Balance	$ 5,449,000
Weighted Average Interest Rate	4.65%
Commercial Real Estate Owner Occupied [Member] \| CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	25
Balance	$ 10,077,000
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] \| CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	12
Balance	$ 24,122,000
Weighted Average Interest Rate	4.86%
Residential Real Estate [Member] \| CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2
Balance	$ 184,000
Weighted Average Interest Rate	4.91%
Farm Real Estate [Member] \| CARESAct [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1
Balance	$ 89,000
Weighted Average Interest Rate	5.00%

Financing receivable, modifications, weighted average interest rate.

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+ References

No definition available.

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Amount of financing receivable modified as troubled debt restructuring.

+ 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=118936363&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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