Loans - Impaired Loans Classified as Troubled Debt Restructured (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) Contract Loan	Dec. 31, 2021 USD ($) Contract Loan
Financing Receivable Modifications [Line Items]
Number of Contracts Modified in the Last 12 Months \| Loan	3	3
Consumer Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts Modified in the Last 12 Months \| Contract	1
Pre-Modification Outstanding Recorded Investment	$ 95
Post-Modification Outstanding Recorded Investment	$ 95
Agricultural Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts Modified in the Last 12 Months \| Contract		1
Pre-Modification Outstanding Recorded Investment		$ 1,655
Post-Modification Outstanding Recorded Investment		$ 1,655
Commercial and Industrial [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts Modified in the Last 12 Months \| Contract	2	1
Pre-Modification Outstanding Recorded Investment	$ 1,232	$ 1,000
Post-Modification Outstanding Recorded Investment	$ 1,232	$ 1,000
Commercial Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts Modified in the Last 12 Months \| Contract	1	1
Pre-Modification Outstanding Recorded Investment	$ 74	$ 382
Post-Modification Outstanding Recorded Investment	$ 74	$ 382

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Number of financing receivables that have been modified by troubled debt restructurings.

+ 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 https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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