Loans and Allowance for Credit Losses - Summary of Loans Individually Evaluated (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss [Line Items]
ACL Allocation	$ 0	$ 116
Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
ACL Allocation	0	9
Land Development and SIDs
Financing Receivable, Allowance for Credit Loss [Line Items]
ACL Allocation	0	39
Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	82	1,316
Real Estate \| Real Estate - Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	0	359
Real Estate \| Real Estate - Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	79	150
ACL Allocation		68
Real Estate \| Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	3
Real Estate \| Land Development and SIDs
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	0	807
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	0	13
Other \| Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated, Recorded investment in loans	$ 0	$ 13

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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