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Loans Receivable and ACL Text Tag (Details)	12 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		0
Financing Receivable, Modifications, Recorded Investment	$ 6,800,000	$ 7,600,000
FNMA & 3rd party loans excluded from financial statements	11,600,000	12,600,000
Number of Loans Originated Under the Paycheck Protection Program			420
Loans Originated Under the Paycheck Protection Program, Amount			$ 57,100,000
Other non-performing asset	$ 52,000	$ 60,000
Number of Real Estate Properties	1	1
Loans held-for-sale (HFS)	$ 0	$ 0
Loans 90 Days Past Due and Still Accruing		$ 0
Modified Loan Subsequently Defaulted	0	0
Loans and Leases Receivable, Related Parties	$ 0
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Purchase	$ 31,500,000	$ 14,300,000
Performing
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	3
Financing Receivable, Modifications, Recorded Investment	$ 5,700,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Purchase		5,800,000
Business
Financing Receivable, Modifications [Line Items]
Overdrafts	73,000	11,000
Accounts, Notes, Loans and Financing Receivable [Line Items]
Overdrafts	73,000	11,000
Financing Receivable, Purchase		600,000
Consumer
Financing Receivable, Modifications [Line Items]
Overdrafts	15,000	19,000
Accounts, Notes, Loans and Financing Receivable [Line Items]
Overdrafts	15,000	19,000
Financing Receivable, Purchase	11,300,000
One-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Purchase	20,000,000	4,000,000
Financing Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	48,000,000
Non-performing
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 1,100,000	$ 1,600,000

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FNMA & 3rd party loans excluded from financial statements

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Represents the aggregate dollar amount of loans that have been originated under the Paycheck Protection Program

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Number of Loans Originated Under the Paycheck Protection Program

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Other non-performing asset

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Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

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

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Number of financing receivables that have been modified by troubled debt restructurings.

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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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The number of real estate properties owned as of the balance sheet date.

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