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Loans - Impaired Loans Classified as Troubled Debt Restructured (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) Loan Contract | Dec. 31, 2020 USD ($) Loan Contract
Financing Receivable Modifications [Line Items] |  |
Number of Contracts Modified in the Last 12 Months | Loan | 3 | 4
Agricultural Real Estate [Member] |  |
Financing Receivable Modifications [Line Items] |  |
Number of Contracts Modified in the Last 12 Months | Contract | 1 | 2
Pre-Modification Outstanding Recorded Investment | $ 1,655 | $ 5,380
Post-Modification Outstanding Recorded Investment | $ 1,655 | $ 5,380
Commercial and Industrial [Member] |  |
Financing Receivable Modifications [Line Items] |  |
Number of Contracts Modified in the Last 12 Months | Contract | 1 | 1
Pre-Modification Outstanding Recorded Investment | $ 1,000 | $ 50
Post-Modification Outstanding Recorded Investment | $ 1,000 | $ 50
Agricultural [Member] |  |
Financing Receivable Modifications [Line Items] |  |
Number of Contracts Modified in the Last 12 Months | Contract |  | 1
Pre-Modification Outstanding Recorded Investment |  | $ 164
Post-Modification Outstanding Recorded Investment |  | $ 164
Commercial Real Estate [Member] |  |
Financing Receivable Modifications [Line Items] |  |
Number of Contracts Modified in the Last 12 Months | Contract | 1 | 2
Pre-Modification Outstanding Recorded Investment | $ 382 | $ 981
Post-Modification Outstanding Recorded Investment | $ 382 | $ 981

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- Definition 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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + 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=123577603&loc=SL6953676-111524 + Details
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- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + 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=123577603&loc=SL6953676-111524 + Details
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