Loans Receivable, Net Loans Receivable, Net - TDRs (Details) $ in Thousands	12 Months Ended
Mar. 31, 2023 USD ($)	Mar. 31, 2022
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	3	0
One-to-four family
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	3
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 1,357

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.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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