Loans Receivable, Net - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	$ 5,624	$ 5,140
Charge-offs	(727)	(257)
Recoveries	232	138
Provision for loan losses	100	603
Allowance for loan losses - Ending Balance	5,229	5,624
Allowance for Loan Losses, Collectively Evaluated for Impairment	4,918	5,555
Allowance for Loan Losses, Individually Evaluated for Impairment	311	69
Loans, gross	597,896	579,504
Loans Receivable, Collectively Evaluated for Impairment	579,708	568,057
Loans Receivable, Individually Evaluated for Impairment	18,188	11,447
One-to-four family
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	731	1,058
Charge-offs	0	0
Recoveries	90	13
Provision for loan losses	(105)	(340)
Allowance for loan losses - Ending Balance	716	731
Allowance for Loan Losses, Collectively Evaluated for Impairment	607	731
Allowance for Loan Losses, Individually Evaluated for Impairment	109	0
Loans, gross	65,808	70,261
Loans Receivable, Collectively Evaluated for Impairment	60,805	65,369
Loans Receivable, Individually Evaluated for Impairment	5,003	4,892
Multifamily
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	1,114	880
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	(5)	234
Allowance for loan losses - Ending Balance	1,109	1,114
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,109	1,114
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Loans, gross	179,117	162,261
Loans Receivable, Collectively Evaluated for Impairment	179,046	161,746
Loans Receivable, Individually Evaluated for Impairment	71	515
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	1,157	907
Charge-offs	(586)	0
Recoveries	10	0
Provision for loan losses	1,233	250
Allowance for loan losses - Ending Balance	1,814	1,157
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,814	1,157
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Loans, gross	178,424	175,313
Loans Receivable, Collectively Evaluated for Impairment	171,234	175,313
Loans Receivable, Individually Evaluated for Impairment	7,190	0
Business
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	2,497	1,855
Charge-offs	0	0
Recoveries	127	102
Provision for loan losses	(1,485)	540
Allowance for loan losses - Ending Balance	1,139	2,497
Allowance for Loan Losses, Collectively Evaluated for Impairment	937	2,428
Allowance for Loan Losses, Individually Evaluated for Impairment	202	69
Loans, gross	166,908	170,031
Loans Receivable, Collectively Evaluated for Impairment	160,985	163,991
Loans Receivable, Individually Evaluated for Impairment	5,923	6,040
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	123	165
Charge-offs	(141)	(257)
Recoveries	5	23
Provision for loan losses	462	192
Allowance for loan losses - Ending Balance	449	123
Allowance for Loan Losses, Collectively Evaluated for Impairment	449	123
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Loans, gross	7,639	1,638
Loans Receivable, Collectively Evaluated for Impairment	7,638	1,638
Loans Receivable, Individually Evaluated for Impairment	1	0
Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - Beginning Balance	2	275
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	0	(273)
Allowance for loan losses - Ending Balance	2	2
Allowance for Loan Losses, Collectively Evaluated for Impairment	2	2
Allowance for Loan Losses, Individually Evaluated for Impairment	0	0
Loans, gross	0	0
Loans Receivable, Collectively Evaluated for Impairment	0	0
Loans Receivable, Individually Evaluated for Impairment	$ 0	$ 0

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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