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Loans - Risk Category of Loans by Portfolio Class (Detail) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans after net deferred loan fees and costs | $ 2,540,398 | $ 2,578,472
Agricultural Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans after net deferred loan fees and costs | 227,150 | 223,479
Agricultural [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans after net deferred loan fees and costs | 127,913 | 132,763
Commercial Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans after net deferred loan fees and costs | $ 1,301,981 | $ 1,335,075

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + 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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-4 + Details
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