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Loans and ACL (Summary of Loan Modifications by Type) (Details)	Mar. 31, 2023 USD ($)
Interest Rate Below Market Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	$ 0
Financing Receivable Modification Percentage of Portfolio Segment	0
Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	271,000
Financing Receivable Modification Percentage of Portfolio Segment	0.0047
Agricultural Mortgage, Portfolio Segment | Interest Rate Below Market Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Agricultural Mortgage, Portfolio Segment | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Agricultural Mortgage, Portfolio Segment | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	232,000
Financing Receivable Modification Percentage of Portfolio Segment	0.0033
Agricultural Other Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Agricultural Other Portfolio Segment [Member] | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Agricultural Other Portfolio Segment [Member] | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	34,000
Financing Receivable Modification Percentage of Portfolio Segment	0.0014
Residential Real Estate, Senior Lein, Portfolio Segment | Interest Rate Below Market Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Residential Real Estate, Senior Lein, Portfolio Segment | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	0
Financing Receivable Modification Percentage of Portfolio Segment	0
Residential Real Estate, Senior Lein, Portfolio Segment | Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Amortized Cost	5,000
Financing Receivable Modification Percentage of Portfolio Segment	$ 0

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