Loans - Major classifications of loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 480,856	$ 478,920
Allowance for loan losses	(3,313)	(3,409)	$ (3,613)
Net Loans	$ 477,543	$ 475,511
Percentage of loans	100.00%	100.00%
Residential real estate \| 1-4 Family
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 135,046	$ 147,143
Allowance for loan losses	$ (486)	$ (506)	(709)
Percentage of loans	28.08%	30.72%
Residential real estate \| Home equity and HELOCs
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 32,684	$ 32,590
Allowance for loan losses	$ (113)	$ (113)	(133)
Percentage of loans	6.79%	6.80%
Residential real estate \| Construction Residential
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 9,113	$ 14,778
Allowance for loan losses	$ (214)	$ (386)	(487)
Percentage of loans	1.90%	3.09%
Commercial real estate \| 1 - 4 family investor
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 98,160	$ 96,508
Allowance for loan losses	$ (569)	$ (527)	(843)
Percentage of loans	20.41%	20.15%
Commercial real estate \| Multi-family (five or more)
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 15,281	$ 13,015
Allowance for loan losses	$ (89)	$ (110)	(159)
Percentage of loans	3.18%	2.72%
Commercial real estate \| Commercial non-residential
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 157,555	$ 158,294
Allowance for loan losses	$ (1,420)	$ (1,451)	(854)
Percentage of loans	32.77%	33.05%
Commercial real estate \| Construction and Land
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 15,584	$ 4,942
Allowance for loan losses	$ (281)	$ (166)	(362)
Percentage of loans	3.24%	1.03%
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 15,433	$ 9,411
Allowance for loan losses	$ (82)	$ (100)	(51)
Percentage of loans	3.21%	1.97%
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total Loans	$ 2,000	$ 2,239
Allowance for loan losses	$ (59)	$ (50)	$ (15)
Percentage of loans	0.42%	0.47%

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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