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Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Jun. 30, 2024 USD ($) Banking_Office	Jun. 30, 2023 USD ($)	Jul. 01, 2022 USD ($)	Jun. 30, 2022 USD ($)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Number of full service banking offices \| Banking_Office	7
Liquid investments with original maturity period	3 months
Accrual of interest on loans due discontinued period, in days	90 days
Percentage of minimum likelihood of realized tax benefit upon settlement	50.00%
Cash, Uninsured Amount	$ 350,000
Federal home loan bank stock and federal reserve bank stock	4,600,000
Long-Lived Asset Impairment	0	$ 0
Retained earnings (accumulated deficit)	43,876,000	43,365,000
Allowance for loan losses	7,499,000	7,139,000		$ 7,052,000
Allowance for credit losses on off-balance sheet credit exposure	$ 98,000	$ 216,000
Accounting Standards Update 2016-13 [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Retained earnings (accumulated deficit)			$ 388,000
Allowance for loan losses			47,000
Allowance for credit losses on off-balance sheet credit exposure			$ 496,000
Sales [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Percentage of major customer revenues	10.00%