Loans and Allowance for Credit Losses - Amortized Cost Basis of Collateral-Dependent Loans by Class of Loans Individually Evaluated (Details) $ in Thousands	Mar. 31, 2025 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 13,002
Allowance for Credit Losses	397
Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	5,951
Allowance for Credit Losses	51
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	1,234
Allowance for Credit Losses	337
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	5,817
Real Estate \| Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
Real Estate \| Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
Business Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	7,185
Business Assets \| Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	5,951
Business Assets \| Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	1,234
Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	5,817
Allowance for Credit Losses	9
Real Estate Loan \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	575
Allowance for Credit Losses	0
Real Estate Loan \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	4,194
Allowance for Credit Losses	9
Real Estate Loan \| Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	5,817
Real Estate Loan \| Real Estate \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	575
Real Estate Loan \| Real Estate \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	4,194
Real Estate Loan \| Business Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
Real Estate Loan \| Business Assets \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
Real Estate Loan \| Business Assets \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
1-4 Family \| Real Estate Loan \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	166
Allowance for Credit Losses	0
1-4 Family \| Real Estate Loan \| Real Estate \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	166
1-4 Family \| Real Estate Loan \| Business Assets \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	0
Multifamily \| Real Estate Loan \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	882
Allowance for Credit Losses	0
Multifamily \| Real Estate Loan \| Real Estate \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	882
Multifamily \| Real Estate Loan \| Business Assets \| Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 0

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