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Loans - Distribution of Fixed Rate Loans and Variable Rate Loans by Major Loan Category (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Consumer Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | $ 330,689 | $ 354,420
Distribution of variable rate loans by major loan category, Variable Rate | 182,284 | 140,003
Agricultural Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 128,681 | 144,702
Distribution of variable rate loans by major loan category, Variable Rate | 96,991 | 76,117
Agricultural [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 57,301 | 52,867
Distribution of variable rate loans by major loan category, Variable Rate | 66,434 | 75,866
Commercial Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 1,013,000 | 941,927
Distribution of variable rate loans by major loan category, Variable Rate | 291,118 | 210,676
Commercial and Industrial [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 141,010 | 130,513
Distribution of variable rate loans by major loan category, Variable Rate | 109,881 | 111,847
Consumer [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 82,956 | 88,972
Distribution of variable rate loans by major loan category, Variable Rate | 68 | 175
Other Loan [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Distribution of fixed rate loans by major loan category, Fixed Rate | 21,499 | 20,029
Distribution of variable rate loans by major loan category, Variable Rate | $ 9,584 | $ 9,789

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- Definition Amount of loan with fixed rate of interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-2 + Details
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- Definition Amount of loan with variable or adjustable rate of interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-2 + Details
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