Loans Receivable and ACL (Details) - USD ($) $ in Thousands		Dec. 31, 2023	Sep. 30, 2023	Mar. 31, 2023		Dec. 31, 2022	Sep. 30, 2022	Mar. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 624,651		$ 597,896
Loans and Leases Receivable, Allowance			$ (6,007)	(5,229)		$ (5,154)	$ (5,509)	$ (5,624)
Loans and Leases Receivable, Net Amount				$ 592,667
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		624,651
Allowance for Credit Loss, Excluding Accrued Interest		5,897
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss		$ 618,754
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		$ 84,041		$ 65,808
Loans and Leases Receivable, Allowance			(2,264)	$ (716)		(724)	(704)	(731)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		84,041
Allowance for Credit Loss, Excluding Accrued Interest		$ 2,068
Percentage of Loan Type		13.40%		11.00%
Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 177,772		$ 179,117
Loans and Leases Receivable, Allowance			(721)	$ (1,109)		(1,080)	(1,055)	(1,114)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		177,772
Allowance for Credit Loss, Excluding Accrued Interest		$ 722
Percentage of Loan Type		28.50%		30.00%
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 174,202		$ 178,424
Loans and Leases Receivable, Allowance			(1,212)	$ (1,814)		(1,045)	(1,608)	(1,157)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		174,202
Allowance for Credit Loss, Excluding Accrued Interest		$ 1,211
Percentage of Loan Type		27.90%		29.80%
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 1,559		$ 0
Loans and Leases Receivable, Allowance			0	$ 0
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss		1,559
Allowance for Credit Loss, Excluding Accrued Interest		$ 1
Percentage of Loan Type		0.20%		0.00%
Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 172,204		$ 166,908	[1]
Loans and Leases Receivable, Allowance			(1,393)	$ (1,139)		(1,913)	(1,814)	(2,497)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	[1]	172,204
Allowance for Credit Loss, Excluding Accrued Interest		$ 1,452
Percentage of Loan Type	[1]	27.60%		27.90%
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income		$ 14,873		$ 7,639	[2]
Loans and Leases Receivable, Allowance			$ (417)	$ (449)		$ (121)	$ (82)	$ (123)
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	[2]	14,873
Allowance for Credit Loss, Excluding Accrued Interest		$ 443
Percentage of Loan Type	[2]	2.40%		1.30%

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

[2] 2) Includes personal loans and consumer overdrafts