Loans and Allowance for Credit Losses - Schedule of Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	$ 1,641	$ 1,329
Nonaccrual with no Allowance for Credit Loss	1,641	1,213
Nonaccrual with allowance for Credit Loss	0	116
Interest Income Recognized During the Period	1	66
Commercial Real Estate Portfolio Segment \| Real Estate - Commercial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period		359
Nonaccrual with no Allowance for Credit Loss		359
Nonaccrual with allowance for Credit Loss		0
Interest Income Recognized During the Period		29
Commercial Real Estate Portfolio Segment \| Real Estate - Residential
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	9	150
Nonaccrual with no Allowance for Credit Loss	9	81
Nonaccrual with allowance for Credit Loss	0	69
Interest Income Recognized During the Period	1	10
Commercial Non Real Estate Portfolio Segment \| Commercial - Non Real Estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period		13
Nonaccrual with no Allowance for Credit Loss		5
Nonaccrual with allowance for Credit Loss		8
Interest Income Recognized During the Period		0
Consumer Portfolio Segment \| Other Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period		807
Nonaccrual with no Allowance for Credit Loss		768
Nonaccrual with allowance for Credit Loss		39
Interest Income Recognized During the Period		$ 27
Agricultural Portfolio Segment \| Agricultural
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	1,632
Nonaccrual with no Allowance for Credit Loss	1,632
Nonaccrual with allowance for Credit Loss	0
Interest Income Recognized During the Period	$ 0

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