Loans Receivable and ACL (Details) - USD ($) $ in Thousands		Jun. 30, 2023	Mar. 31, 2023		Jun. 30, 2022	Mar. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 590,534	$ 597,896
Loans and Leases Receivable, Allowance			(5,229)		$ (5,604)	$ (5,624)
Loans and Leases Receivable, Net Amount			$ 592,667
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		590,534
Allowance for Credit Loss, Excluding Accrued Interest		5,858
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss		$ 584,676
Percentage of Loan Type		100.00%	100.00%
One-to-four family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 65,526	$ 65,808
Loans and Leases Receivable, Allowance			$ (716)		(649)	(731)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		65,526
Allowance for Credit Loss, Excluding Accrued Interest		$ 2,063
Percentage of Loan Type		11.10%	11.00%
Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 178,815	$ 179,117
Loans and Leases Receivable, Allowance			$ (1,109)		(1,053)	(1,114)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		178,815
Allowance for Credit Loss, Excluding Accrued Interest		$ 713
Percentage of Loan Type		30.30%	30.00%
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 173,088	$ 178,424
Loans and Leases Receivable, Allowance			$ (1,814)		(1,108)	(1,157)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		173,088
Allowance for Credit Loss, Excluding Accrued Interest		$ 1,264
Percentage of Loan Type		29.30%	29.80%
Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 163,348	$ 166,908	[1]
Loans and Leases Receivable, Allowance			$ (1,139)		(2,321)	(2,497)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	[1]	163,348
Allowance for Credit Loss, Excluding Accrued Interest		$ 1,404
Percentage of Loan Type	[1]	27.70%	27.90%
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 9,757	$ 7,639	[2]
Loans and Leases Receivable, Allowance			$ (449)		$ (113)	$ (123)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	[2]	9,757
Allowance for Credit Loss, Excluding Accrued Interest		$ 414
Percentage of Loan Type	[2]	1.60%	1.30%

[1] (1) Includes PPP loans and business overdrafts

[2] 2) Includes personal loans and consumer overdrafts