Loans and Allowance for Credit Losses - Schedule of Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Dec. 31, 2024	Mar. 31, 2024
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	$ 3,775	$ 537
Nonaccrual with no Allowance for Credit Loss	2,350	436
Nonaccrual with allowance for Credit Loss	1,425	101
Interest Income Recognized During the Period	42	6
Commercial Real Estate Portfolio Segment \| Real Estate - Commercial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	2,334	419
Nonaccrual with no Allowance for Credit Loss	2,334	419
Interest Income Recognized During the Period	23	4
Commercial Real Estate Portfolio Segment \| Real Estate - Residential
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	87	98
Nonaccrual with no Allowance for Credit Loss	16	17
Nonaccrual with allowance for Credit Loss	71	81
Interest Income Recognized During the Period	5	2
Commercial Non Real Estate Portfolio Segment \| Commercial - Non Real Estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	6	16
Nonaccrual with allowance for Credit Loss	6	16
Interest Income Recognized During the Period	3
Consumer Portfolio Segment \| Other Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period		4
Nonaccrual with allowance for Credit Loss		$ 4
Land Development And SIDs Portfolio Segment \| Land Development and SIDs
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans end of period	1,348
Nonaccrual with no Allowance for Credit Loss	0
Nonaccrual with allowance for Credit Loss	1,348
Interest Income Recognized During the Period	$ 11

Financing receivable nonaccrual with allowance.

No definition available.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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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/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Name Regulation S-K (SK)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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