Loans and Allowance for Credit Losses - Summary of Loans by Major Category (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Past Due [Line Items]
Total Loans	$ 448,406	$ 402,215
Allowance for credit losses	(5,809)	(5,441)	$ (5,860)
Net deferred origination costs & fees	(60)	(18)
Loans, net	442,537	396,756
Real Estate \| Construction
Financing Receivable, Past Due [Line Items]
Total Loans	28,633	15,069
Allowance for credit losses	(356)	(246)	(246)
Real Estate \| Commercial
Financing Receivable, Past Due [Line Items]
Total Loans	129,235	120,184
Allowance for credit losses	(1,787)	(1,572)	(2,245)
Real Estate \| Residential
Financing Receivable, Past Due [Line Items]
Total Loans	162,041	161,144
Allowance for credit losses	(1,784)	(1,926)	(1,829)
Commercial \| Non-Real Estate
Financing Receivable, Past Due [Line Items]
Total Loans	48,378	32,007
Allowance for credit losses	(991)	(667)	(759)
Agriculture
Financing Receivable, Past Due [Line Items]
Total Loans	54,655	42,835
Allowance for credit losses	(558)	(476)	(228)
Other Consumer
Financing Receivable, Past Due [Line Items]
Total Loans	10,158	14,649
Allowance for credit losses	(135)	(262)	(327)
Land Development and Sanitary & Improvement Districts (SIDs)
Financing Receivable, Past Due [Line Items]
Total Loans	15,306	16,327
Allowance for credit losses	$ (198)	$ (292)	$ (226)

Loans and leases receivable deferred origination cost and fees net.

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