Borrowings - Additional Information (Details) - USD ($)	Dec. 31, 2025	Mar. 31, 2025
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 0	$ 0
Remaining availability for FHLB borrowings	47,000,000	40,500,000
Remaining availability for FRB borrowings	10,000,000
Pledged commercial real estate loans carrying value of borrowings through discount window	23,000,000
FHLB of Topeka
Line of Credit Facility [Line Items]
Outstanding borrowings	0	0
Investment Securities Pledged
Line of Credit Facility [Line Items]
FHLB borrowings, collateral for advances	27,000
Loans Pledged
Line of Credit Facility [Line Items]
FHLB borrowings, collateral for advances	80,000,000
Private Banker's Bank
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 5,000,000	$ 5,000,000

Federal reserve bank advances general debt obligations disclosures amount of available unused funds.

No definition available.

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- Definition

Pledged commercial real estate loans carrying value of borrowings through discount window.

+ References

No definition available.

+ Details

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- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

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-SubTopic 210
-Name Accounting Standards Codification
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-Subparagraph (SX 210.9-03(16))
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- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Details

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