Loans and Allowance for Credit Losses - Schedule of Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	$ 5,523	$ 5,858	$ 5,441	$ 5,860	$ 5,860
Provision for (reversal of) credit losses	0	57	86	56
Loans Charged off	0	0	(7)	(4)
Recoveries	63	0	66	3
Ending Allowance Balance	5,586	5,915	5,586	5,915	5,441
Real Estate \| Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	285	289	246	246	246
Provision for (reversal of) credit losses	0	(2)	39	41
Ending Allowance Balance	285	287	285	287	246
Real Estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	1,688	2,023	1,572	2,245	2,245
Provision for (reversal of) credit losses	0	60	116	(162)
Ending Allowance Balance	1,688	2,083	1,688	2,083	1,572
Real Estate \| Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	1,800	1,876	1,926	1,829	1,829
Provision for (reversal of) credit losses	(0)	(8)	(126)	39
Ending Allowance Balance	1,800	1,868	1,800	1,868	1,926
Commercial \| Non-Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	795	658	667	759	759
Provision for (reversal of) credit losses	0	(14)	128	(115)
Ending Allowance Balance	795	644	795	644	667
Agriculture
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	559	406	476	228	228
Provision for (reversal of) credit losses	0	82	83	260
Ending Allowance Balance	559	488	559	488	476
Other Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	168	370	262	327	327
Provision for (reversal of) credit losses	(0)	(75)	(90)	(31)
Loans Charged off	0	0	(7)	(4)
Recoveries	0	0	3	3
Ending Allowance Balance	168	295	168	295	262
Land Development and SIDs
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Allowance Balance	228	236	292	226	226
Provision for (reversal of) credit losses	(0)	14	(64)	24
Recoveries	63		63
Ending Allowance Balance	$ 291	$ 250	$ 291	$ 250	$ 292

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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