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Summary of Significant Accounting Policies (Detail) - USD ($)		1 Months Ended	12 Months Ended
	Jan. 12, 2022	May 20, 2025	Jun. 30, 2025	Jun. 30, 2024
Common stock			$ 65,000	$ 65,000
Number common stock shares sold			2,804,306
Common stock, par value			$ 10
Cash and cash equivalents			$ 24,665,000	26,959,000
Debt instrument, percentage			80.00%
Accrued interest receivable on ESOP loan			$ 1,451,000	$ 1,398,000
Antidilutive securities			0	0
Debt instrument, term			25 years
Accrued expenses and other liabilities			$ 3,926,000	$ 3,796,000
Merger agreement company name		15 Beach
Interest penalties			0	0
Federal Reserve Bank
Cash and cash equivalents			18,469,000	22,682,000
Allowance for credit losses for loans [Member]
Accrued interest receivable on ESOP loan			581,000	$ 520,000
Common Stock [Member]
Percentage of stock contributed to charitable foundation	2.00%
Percentage of stock offered for sale	43.00%
Common stock			$ 28,000,000
Receive cash for each share		$ 14.25
Second mortgages and home equity lines of credit [Member]
Home equity lines of credit			80.00%
Lines of credit, percentage			80.00%
Second mortgages and home equity lines of credit [Member] \| Maximum [Member]
Debt instrument, term			20 years
Second mortgages and home equity lines of credit [Member] \| Minimum [Member]
Debt instrument, term			15 years